BioMed Research International: Biomaterials The latest articles from Hindawi Publishing Corporation © 2016 , Hindawi Publishing Corporation . All rights reserved. Randomized Clinical Trial of Composite Restorations in Primary Teeth: Effect of Adhesive System after Three Years Wed, 19 Oct 2016 12:03:49 +0000 The purpose of this study was to assess the clinical performance of composite restorations placed with different adhesive systems in primary teeth. In 32 patients, 128 composite restorations were placed using a split-mouth design as follows (4 groups/patient): three-step etch-and-rinse (Group 1), two-step etch-and-rinse (Group 2), two-step self-etch (Group 3), and one-step self-etch (Group 4). The restorations were clinically evaluated at baseline and at 6, 18, and 36 months according to the FDI criteria. There was no significant difference between the adhesive systems in retention of the restorations (). Over time, there was a statistically significant decrease in marginal adaptation in all groups, whereas surface and marginal staining significantly increased in Groups 3 and 4 (). The etch-and-rinse adhesive systems resulted in better marginal adaptation than the self-etch adhesive systems (). It was concluded that preetching of the primary enamel might help improve the clinical performance of the self-etch adhesive systems in primary teeth. Secil Bektaş Donmez, Melek D. Turgut, Serdar Uysal, Pinar Ozdemir, Meryem Tekcicek, Brigitte Zimmerli, and Adrian Lussi Copyright © 2016 Secil Bektaş Donmez et al. All rights reserved. Patterning of Endothelial Cells and Mesenchymal Stem Cells by Laser-Assisted Bioprinting to Study Cell Migration Wed, 19 Oct 2016 11:11:05 +0000 Tissue engineering of large organs is currently limited by the lack of potent vascularization in vitro. Tissue-engineered bone grafts can be prevascularized in vitro using endothelial cells (ECs). The microvascular network architecture could be controlled by printing ECs following a specific pattern. Using laser-assisted bioprinting, we investigated the effect of distance between printed cell islets and the influence of coprinted mesenchymal cells on migration. When printed alone, ECs spread out evenly on the collagen hydrogel, regardless of the distance between cell islets. However, when printed in coculture with mesenchymal cells by laser-assisted bioprinting, they remained in the printed area. Therefore, the presence of mesenchymal cell is mandatory in order to create a pattern that will be conserved over time. This work describes an interesting approach to study cell migration that could be reproduced to study the effect of trophic factors. Jean-Michel Bourget, Olivia Kérourédan, Manuela Medina, Murielle Rémy, Noélie Brunehilde Thébaud, Reine Bareille, Olivier Chassande, Joëlle Amédée, Sylvain Catros, and Raphaël Devillard Copyright © 2016 Jean-Michel Bourget et al. All rights reserved. The Effect of Energy Densities on the Shear Bond Strength of Self-Adhering Flowable Composite to Er:YAG Pretreated Dentin Mon, 17 Oct 2016 09:33:26 +0000 Objective. To investigate the shear bond strength of self-adhering flowable resin composite, to dentin, after exposing it to Er:YAG laser radiation, at different energy densities. Materials and Methods. Sixty freshly extracted human third molars were randomly divided into five groups (). In the control group, dentin was left unirradiated, whereas, in the other four groups, dentin was irradiated with Er:YAG laser in noncontact mode (MSP mode = 100 µs; 10 Hz; beam diameter: 1.3 mm; speed of 1 mm/second; air 6 mL/min; and water 4 mL/min), and respectively, with the following level of energy (50 mJ, 60 mJ, 80 mJ, and 100 mJ). Then, self-adhering flowable resin composite was bonded to all prepared dentin surfaces. Shear bond strength (SBS) was applied and fractured surfaces were examined using scanning electron microscopy. Results. SBS values showed significant differences in 60 mJ () compared to other groups. Morphological evaluation revealed tags or plugs in dentinal tubules, especially when 60 mJ and 80 mJ were used. All four groups tended to leave more residues on the dentin surface, than the control group. Conclusion. Er:YAG dentin irradiation may enhance SBS of the self-adhering flowable resin composite when it is used at the appropriate low level of energy density. Paul Nahas, Toni Zeinoun, Zeina Majzoub, Karim Corbani, and Samir Nammour Copyright © 2016 Paul Nahas et al. All rights reserved. In Vitro Comparative Analysis of Fracture Resistance in Inlay Restoration Prepared with CAD-CAM and Different Systems in the Primary Teeth Mon, 17 Oct 2016 06:38:26 +0000 Objective. The aim of this study was to compare to fracture resistance test of inlay restorations prepared using direct inlay technique (Gradia® Direct Composite) and Indirect Restoration System® (Gradia Indirect Composite) and CAD/CAD system (Vita Enamic® Block). Study Design. 48 noncarious extracted maxillary second primary molars were randomly divided into 4 groups with 12 in each group. All the teeth were prepared based on inlay class II preparations except for the control group. Other groups were restored with Gradia Direct Composite, Gradia Indirect Composite, and Vita Enamic Block, respectively. All restorations were cemented self-adhesive dual cure resin (3M Espe, RelyX™ Unicem Aplicap). A fracture test was performed using a compressive load. Results were analyzed using one-way analysis of variance and Duncan’s post hoc multiple comparison tests (). Results. Vita Enamic Block and Gradia Indirect Composite showed significantly higher fracture resistance than Gradia Direct Composite (). There was no significant difference fracture resistance between Vita Enamic Block and Gradia Indirect Composite (). All restorations tested led to a significant reduction in fracture resistance (). Conclusion. In inlay restorations, Indirect Restoration Systems and CAD/CAM systems were applied successfully together with the self-adhesive dual cure resin cements in primary molars. Huseyin Simsek and Sera Derelioglu Copyright © 2016 Huseyin Simsek and Sera Derelioglu. All rights reserved. Retention Strength after Compressive Cyclic Loading of Five Luting Agents Used in Implant-Supported Prostheses Sun, 16 Oct 2016 14:14:06 +0000 The purpose of this study was to evaluate and compare the retention strength of five cement types commonly used in implant-retained fixed partial dentures, before and after compressive cyclic loading. In five solid abutments screwed to 5 implant analogs, 50 metal Cr-Ni alloy copings were cemented with five luting agents: resin-modified glass ionomer (RmGI), resin composite (RC), glass ionomer (GI), resin urethane-based (RUB), and compomer cement (CC). Two tensile tests were conducted with a universal testing machine, one after the first luting of the copings and the other after 100,000 cycles of 100 N loading at 0.72 Hz. The one way ANOVA test was applied for the statistical analysis using the post hoc Tukey test when required. Before and after applying the compressive load, RmGI and RC cement types showed the greatest retention strength. After compressive loading, RUB cement showed the highest percentage loss of retention (64.45%). GI cement recorded the lowest retention strength (50.35 N) and the resin composite cement recorded the highest (352.02 N). The type of cement influences the retention loss. The clinician should give preference to lower retention strength cement (RUB, CC, and GI) if he envisages any complications and a high retention strength one (RmGI, RC) for a specific clinical situation. Angel Alvarez-Arenal, Ignacio Gonzalez-Gonzalez, Hector deLlanos-Lanchares, Aritza Brizuela-Velasco, Javier Pinés-Hueso, and Joseba Ellakuria-Echebarria Copyright © 2016 Angel Alvarez-Arenal et al. All rights reserved. Retrieval Research in Hip and Knee Arthroplasty Sun, 16 Oct 2016 14:02:11 +0000 Thomas M. Grupp, Sandra Utzschneider, and Steven M. Kurtz Copyright © 2016 Thomas M. Grupp et al. All rights reserved. Orthodontics: Bracket Materials, Adhesives Systems, and Their Bond Strength Thu, 13 Oct 2016 09:34:59 +0000 Andrea Scribante, Rosalia Contreras-Bulnes, Mona A. Montasser, and Pekka K. Vallittu Copyright © 2016 Andrea Scribante et al. All rights reserved. A 12-Week Assessment of the Treatment of White Spot Lesions with CPP-ACP Paste and/or Fluoride Varnish Tue, 11 Oct 2016 09:57:44 +0000 This 12-week clinical study evaluated the impact of 10% CPP-ACP and 5% sodium fluoride varnish regimes on the regression of nonorthodontic white spot lesions (WSLs). The study included 21 children with 101 WSLs who were randomised into four treatment regimes: weekly clinical applications of fluoride varnish for the first month (FV); twice daily self-applications of CPP-ACP paste (CPP-ACP); weekly applications of fluoride varnish for the first month and twice daily self-applications of CPP-ACP paste (CPP-ACP-FV); and no intervention (control). All groups undertook a standard oral hygiene protocol and weekly consultation. Visual appraisals and laser fluorescence (LF) measurements were made in weeks one and twelve. The majority of WSLs in the control and FV groups exhibited no shift in appearance, whereas, in the CPP-ACP and CPP-ACP-FV groups, the lesions predominantly regressed. The visual and LF assessments indicated that the extent of remineralisation afforded by the treatments was of the following order: control ~ FV < CPP-ACP ~ CPP-ACP-FV. Self-applications of CPP-ACP paste as an adjunct to standard oral hygiene significantly improved the appearance and remineralisation of WSLs. No advantage was observed for the use of fluoride varnish as a supplement to either the standard or CPP-ACP-enhanced oral hygiene regimes. Zeynep Aslı Güçlü, Alev Alaçam, and Nichola Jayne Coleman Copyright © 2016 Zeynep Aslı Güçlü et al. All rights reserved. Clinical and Histological Evaluation of Direct Pulp Capping on Human Pulp Tissue Using a Dentin Adhesive System Mon, 10 Oct 2016 13:19:14 +0000 Objective. This study presents a clinical and histological evaluation of human pulp tissue responses after direct capping using a new dentin adhesive system. Methods. Twenty-eight caries-free third molar teeth scheduled for extraction were evaluated. The pulps of 22 teeth were mechanically exposed and randomly assigned to 1 of 2 groups: Single Bond Universal or calcium hydroxide. Another group of 6 teeth acted as the intact control group. The periapical response was assayed, and a clinical examination was performed. The teeth were extracted after 6 weeks, and a histological analysis was performed. The pulp status was assessed, and the thickness of the dentin bridge was measured and categorized using a histological scoring system. Results. The clinical phase was asymptomatic for Single Bond Universal patients. Patients in the calcium hydroxide group reported mild symptoms of pain, although the histological examination revealed that dentin bridges with or without limited pulpitis had begun forming in each tooth. The universal adhesive system exhibited nonsignificantly increased histological signs of pulpitis () and a significantly weaker thin mineralized tissue layer () compared with the calcium hydroxide group. Conclusion. The results suggest that Single Bond Universal is inappropriate for human pulp capping; however, further long-term studies are needed to determine the biocompatibility of this agent. Alicja Nowicka, Ryta Łagocka, Mariusz Lipski, Mirosław Parafiniuk, Katarzyna Grocholewicz, Ewa Sobolewska, Agnieszka Witek, and Jadwiga Buczkowska-Radlińska Copyright © 2016 Alicja Nowicka et al. All rights reserved. Evaluation of the Elastic Properties of Thirteen Silicone Interocclusal Recording Materials Mon, 26 Sep 2016 16:49:01 +0000 Background. Addition silicones are popular as dental impression materials and are used in bite registration procedures. Objective. This study aimed to compare the postsetting elasticities and other mechanical properties of thirteen addition silicone interocclusal recording materials. Materials and Methods. The following materials were investigated: Colorbite D, Futar D, Genie Bite, Jet Blue Bite fast, Memoreg 2, O-Bite, Occlufast Rock, Omni-Bite Plus, Regidur i, Registrado X-tra, Regofix transparent, StoneBite, and Variotime Bite. Thirty specimens of each material were tested. The elasticities and strengths of the materials were measured with a universal testing machine, and computer software was used to determine the E-moduli, ultimate tensile strengths, and ultimate elongations of the specimens. Results. The results were subjected to statistical analysis using the Kruskal-Wallis test (). The statistics revealed that the mean E-modulus values varied significantly across the materials () and were highest for the StoneBite and Registrado X-tra and lowest for the Regofix transparent. The ultimate tensile strengths were highest for the Regofix transparent and Registrado X-tra () and lowest for the Jet Blue Bite fast and Memoreg 2 (). The elongation percentages at the point of breaking varied significantly across the materials (); the lowest value was observed for the StoneBite, whereas the Regofix transparent nearly doubled original length. Conclusions. The authors concluded that materials with the high E-moduli and great ultimate tensile strengths may be most useful clinically. Registrado X-tra and StoneBite best met these criteria. Mieszko Wieckiewicz, Natalia Grychowska, Marek Zietek, and Wlodzimierz Wieckiewicz Copyright © 2016 Mieszko Wieckiewicz et al. All rights reserved. Resin Bonding of Self-Etch Adhesives to Bovine Dentin Bleached from Pulp Chamber Mon, 26 Sep 2016 14:27:53 +0000 This study evaluated the microtensile bond strength (μTBS) of 1-step self-etch adhesives (1-SEAs) and 2-step self-etch adhesives (2-SEAs) to pulp chamber dentin immediately after bleaching with 2 types of common bleaching techniques. Pulp chamber dentin of bovine teeth was bleached using 30% hydrogen peroxide (H2O2) solution with quartz-tungsten-halogen light-curing unit (Group 1) and 3.5% H2O2-containing titanium dioxide (TiO2) (Pyrenees®) activated with 405-nm violet diode laser for 15 min (Group 2). Unbleached specimens were placed in distilled water for 15 min and used as controls. After treatment, dentin was bonded with resin composite using 1-SEA or 2-SEA and stored in water at 37°C for 24 h. Each specimen was sectioned and trimmed to an hourglass-shape and μTBS was measured. Fractured specimens were examined under a scanning electron microscope to determine fracture modes. All specimens in Group 1 failed before proper bonding tests. In Group 2, the μTBS of 2-SEA was significantly greater (with no failed specimens) than 1-SEA (where 21 out of 36 failed). These results indicate that 2-SEA is a better adhesive system than 1-SEA on bleached dentin. Our results also demonstrated that application of H2O2 significantly decreases bond strength of resin to dentin; however, in the case of nonvital tooth bleaching, Pyrenees® is a better alternative to the conventional 30% H2O2 bleaching. Akiko Haruyama, Atsushi Kameyama, Junji Kato, Shinji Takemoto, Yutaka Oda, Eiji Kawada, Toshiyuki Takahashi, and Masahiro Furusawa Copyright © 2016 Akiko Haruyama et al. All rights reserved. Bonding of Metal Orthodontic Attachments to Sandblasted Porcelain and Zirconia Surfaces Thu, 22 Sep 2016 13:34:39 +0000 This study evaluates tensile bond strength (TBS) of metal orthodontic attachments to sandblasted feldspathic porcelain and zirconia with various bonding protocols. Thirty-six (36) feldspathic and 36 zirconia disc samples were prepared, glazed, embedded in acrylic blocks and sandblasted, and divided into three groups according to one or more of the following treatments: hydrofluoric acid 4% (HF), Porcelain Conditioner silane primer, Reliance Assure® primer, Reliance Assure plus® primer, and Z Prime™ plus zirconia primer. A round traction hook was bonded to each sample. Static tensile bond strength tests were performed in a universal testing machine and adhesive remnant index (ARI) scoring was done using a digital camera. One-way ANOVA and Pearson chi-square tests were used to analyze TBS (MPa) and ARI scores. No statistically significant mean differences were found in TBS among the different bonding protocols for feldspathic and zirconia, values = 0.369 and 0.944, respectively. No statistically significant distribution of ARI scores was found among the levels of feldspathic, value = 0.569. However, statistically significant distribution of ARI scores was found among the levels of zirconia, value = 0.026. The study concluded that silanization following sandblasting resulted in tensile bond strengths comparable to other bonding protocols for feldspathic and zirconia surface. Amitoj S. Mehta, Carla A. Evans, Grace Viana, Ana Bedran-Russo, and Maria Therese S. Galang-Boquiren Copyright © 2016 Amitoj S. Mehta et al. All rights reserved. Shear Bond Strength of Three Orthodontic Bonding Systems on Enamel and Restorative Materials Wed, 21 Sep 2016 12:17:13 +0000 Objective. The aim of this in vitro study was to determine the shear bond strength (SBS) and adhesive remnant index (ARI) score of two self-etching no-mix adhesives (iBond™ and Scotchbond™) on different prosthetic surfaces and enamel, in comparison with the commonly used total etch system Transbond XT™. Materials and Methods. A total of 270 surfaces (1 enamel and 8 restorative surfaces, ) were randomly divided into three adhesive groups. In group 1 (control) brackets were bonded with Transbond XT primer. In the experimental groups iBond adhesive (group 2) and Scotchbond Universal adhesive (group 3) were used. The SBS was measured using a Zwicki 1120™ testing machine. The ARI and SBS were compared statistically using the Kruskal–Wallis test (). Results. Significant differences in SBS and ARI were found between the control group and experimental groups. Conclusions. Transbond XT showed the highest SBS on human enamel. Scotchbond Universal on average provides the best bonding on all other types of surface (metal, composite, and porcelain), with no need for additional primers. It might therefore be helpful for simplifying bonding in orthodontic procedures on restorative materials in patients. If metal brackets have to be bonded to a metal surface, the use of a dual-curing resin is recommended. Andreas Hellak, Jennifer Ebeling, Michael Schauseil, Steffen Stein, Matthias Roggendorf, and Heike Korbmacher-Steiner Copyright © 2016 Andreas Hellak et al. All rights reserved. Radiation-Guided Peptide Delivery in a Mouse Model of Nasopharyngeal Carcinoma Wed, 21 Sep 2016 10:58:34 +0000 Purpose. This study aimed to evaluate the characteristics of the HVGGSSV peptide, exploring radiation-guided delivery in a mouse model of nasopharyngeal carcinoma. Methods. Mice with CNE-1 nasopharyngeal carcinoma were assigned to two different groups treated with Cy7-NHS and Cy7-HVGGSSV, respectively. Meanwhile, each mouse received a single dose of 3 Gy radiation. Biological distribution of the recombinant peptide was assessed on an in vivo small animal imaging system. Results. The experimental group showed maximum fluorescence intensity in irradiated tumors treated with Cy7-labeled HVGGSSV, while untreated (0 Gy) control tumors showed lower intensity levels. Fluorescence intensities of tumors in the right hind limbs of experimental animals were , , , , and photons/s/cm2 higher compared with left hind limb values at 1, 2, 15, 24, and 48 h, respectively. Fluorescence intensities of tumor in the right hind limbs of the experimental group were , , , , and photons/s/cm2 higher compared with control group values at 1, 2, 15, 24, and 48 h, respectively. Fluorescence was not specifically distributed in the control group. Compared with low fluorescence intensity in the heart, lungs, and tumors, high fluorescence distribution was found in the liver and kidney at 48 h. Conclusions. HVGGSSV was selectively bound to irradiated nasopharyngeal carcinoma, acting as a targeting transport carrier for radiation-guided drugs that are mainly metabolized in the kidney and liver. Pei-cheng Lin, Jun-yan He, Yu-yin Le, Kai-xin Du, Wei-feng Zhu, Qing-qin Peng, Ya-ping Dong, Jin-luan Li, and Jun-xin Wu Copyright © 2016 Pei-cheng Lin et al. All rights reserved. Effect of Removal of Enamel on Rebonding Strength of Resin Composite to Enamel Tue, 20 Sep 2016 16:36:59 +0000 Objective. To examine the effect of removing the surface layer of enamel on the rebonding strength of resin composite. Methods. Teeth in four groups () were etched, a small amount of resin composite was bonded and debonded, then specimens in three groups were ground for different lengths of time (10 s, 20 s, 30 s) to remove an increasing amount of enamel, one group was left untouched. The teeth were bonded again and the bond strengths of 1st and 2nd bonding were compared and analysed against the amount of enamel loss in different groups (7 µm (±2); 12 µm (±1); 16 µm (±3)). Specimens were examined with SEM and by noncontacting optical profilometer. Results. Although results indicated higher rebonding strength with increasing enamel removal ANOVA showed low statistical differences between the groups (). However, values between first bonding and rebonding strengths differed significantly () in the group that was not ground. SEM revealed that enamel-surfaces that were ground after debonding etched well, compared to the surfaces that still contained adhesive remnants. Conclusions. Removal of small amount of enamel refreshed the surface for rebonding. Rebonding strengths without grinding the surface before bonding were lower than bond strength to intact enamel. L. Kilponen, L. Lassila, M. Tolvanen, J. Varrela, and P. K. Vallittu Copyright © 2016 L. Kilponen et al. All rights reserved. Backside Wear Analysis of Retrieved Acetabular Liners with a Press-Fit Locking Mechanism in Comparison to Wear Simulation In Vitro Mon, 19 Sep 2016 14:19:41 +0000 Backside wear due to micromotion and poor conformity between the liner and its titanium alloy shell may contribute to the high rates of retroacetabular osteolysis and consequent aseptic loosening. The purpose of our study was to understand the wear process on the backside of polyethylene liners from two acetabular cup systems, whose locking mechanism is based on a press-fit cone in combination with a rough titanium conical inner surface on the fixation area. A direct comparison between in vitro wear simulator tests (equivalent to 3 years of use) and retrieved liners (average 13.1 months in situ) was done in order to evaluate the backside wear characteristics and behavior of these systems. Similar wear scores between in vitro tested and retrieved liners were observed. The results showed that this locking mechanism did not significantly produce wear marks at the backside of the polyethylene liners due to micromotion. In all the analyzed liners, the most common wear modes observed were small scratches at the cranial fixation zone directly below the rough titanium inner surface of the shell. It was concluded that most of the wear marks were produced during the insertion and removal of the liner, rather than during its time in situ. Ana Laura Puente Reyna, Marcus Jäger, Thilo Floerkemeier, Sven Frecher, Karl-Stefan Delank, Christoph Schilling, and Thomas M. Grupp Copyright © 2016 Ana Laura Puente Reyna et al. All rights reserved. Evaluation of Light-Activated Provisional Resin Materials for Periodontal Soft Tissue Management Thu, 08 Sep 2016 17:31:53 +0000 The purpose of this study was to determine mechanical properties using a compressive test with cylinder specimen ( mm and  mm) as well as cytotoxicity using elutes from disk specimen ( mm and  mm) against human gingival fibroblasts and oral keratinocytes with light-activated provisional resin materials (Revotek LC and Luxatemp Solar) compared to chemically activated counterpart (Snap, Trim II, and Jet). Significantly increased compressive strength (210~280 MPa) was detected in light-activated products compared to chemically activated ones (20~65 MPa, ) and similar compressive modulus was detected in both types (0.8~1.5 and 0.5~1.3 GPa). Simultaneously, the light-activated products showed less adverse effects on the periodontal soft tissue cells in any polymerization stage compared to the chemically activated products. Particularly, chemically activated products had significantly greater adverse effects during the “polymerizing” phase compared to those that were “already set” (), as shown in confocal microscopic images of live and dead cells. In conclusion, light-activated provisional resin materials have better mechanical properties as well as biocompatibility against two tested types of oral cells compared to the chemically activated counterpart, which are considered as more beneficial choice for periodontal soft tissue management. Soo-Kyung Jun, Hae-Hyoung Lee, and Jung-Hwan Lee Copyright © 2016 Soo-Kyung Jun et al. All rights reserved. A Facile Approach for the Mass Production of Submicro/Micro Poly (Lactic Acid) Fibrous Mats and Their Cytotoxicity Test towards Neural Stem Cells Tue, 06 Sep 2016 14:27:06 +0000 Despite many of the studies being conducted, the electrospinning of poly (lactic acid) (PLA), dissolved in its common solvents, is difficult to be continuously processed for mass production. This is due to the polymer solution droplet drying. Besides, the poor stretching capability of the polymer solution limits the production of small diameter fibers. To address these issues, we have examined the two following objectives: first, using an appropriate solvent system for the mass production of fibrous mats with fine-tunable fiber diameters; second, nontoxicity of the mats towards Neural Stem Cell (NSC). To this aim, TFA (trifluoroacetic acid) was used as a cosolvent, in a mixture with DCM (dichloromethane), and the solution viscosity, surface tension, electrical conductivity, and the continuity of the electrospinning process were compared with the solutions prepared with common single solvents. The binary solvent facilitated PLA electrospinning, resulting in a long lasting, stable electrospinning condition, due to the low surface tension and high conductivity of the binary-solvent system. The fiber diameter was tailored from nano to micro by varying effective parameters and examined by scanning electron microscopy (SEM) and image-processing software. Laminin-coated electrospun mats supported NSC expansion and spreading, as examined using AlamarBlue assay and fluorescent microscopy, respectively. Afra Hadjizadeh, Houman Savoji, and Abdellah Ajji Copyright © 2016 Afra Hadjizadeh et al. All rights reserved. Failure of Polyethylene Inlays in Cementless Total Hip Arthroplasty: A Retrieval Analysis Wed, 31 Aug 2016 12:53:14 +0000 A retrieval analysis has been performed on 50 polyethylene inlays of cementless screw ring implants (Mecring, Mecron, Berlin, Germany) to investigate the failure mechanism of this specific open cup hip arthroplasty design that has shown a high clinical failure rate. Design-specific damage modes like rim creep, collar fatigue, and backside wear were assessed. Furthermore, the inlays were measured using a CMM to determine deformation. In 90% backside wear was observed and collar fatigue occurred in 68% of the cases. Rim creep was present in 38% of the polyethylene inlays. In 90% of the cases the cup opening diameter was 32.1 mm or less and 46% had a diameter less than 32 mm. It seems that creep and deformation of the polyethylene leads to a reduced diameter at the cup opening and consequently decreased clearance. To avoid this type of failure, polyethylene inlays should be supported at the back by the cup to reduce the risk of ongoing creep deformation. Ulrike Mueller, Christoph Lee, Christian Heisel, Marc Thomsen, Rudi G. Bitsch, and J. Philippe Kretzer Copyright © 2016 Ulrike Mueller et al. All rights reserved. Does the Laser-Microtextured Short Implant Collar Design Reduce Marginal Bone Loss in Comparison with a Machined Collar? Wed, 31 Aug 2016 07:53:22 +0000 Purpose. To compare marginal bone loss between subgingivally placed short-collar implants with machined collars and those with machined and laser-microtextured collars. Materials and Methods. The investigators used a retrospective study design and included patients who needed missing posterior teeth replaced with implants. Short-collar implants with identical geometries were divided into two groups: an M group, machined collar; and an L group, machined and laser-microtextured collar. Implants were evaluated according to marginal bone loss, implant success, and probing depth (PD) at 3 years of follow-up. Results. Sixty-two patients received 103 implants (56 in the M group and 47 in the L group). The cumulative survival rate was 100%. All implants showed clinically acceptable marginal bone loss, although bone resorption was lower in the L group (0.49 mm) than in the M group (1.38 mm) at 3 years (). A significantly shallower PD was found for the implants in the L group during follow-up (). Conclusions. Our results suggest predictable outcomes with regard to bone loss for both groups; however, bone resorption was less in the L group than in the M group before and after loading. The laser-microtextured collar implant may provide a shallower PD than the machined collar implant. B. Alper Gultekin, Ali Sirali, Pinar Gultekin, Serdar Yalcin, and Eitan Mijiritsky Copyright © 2016 B. Alper Gultekin et al. All rights reserved. Silver-Coated Hip Megaprosthesis in Oncological Limb Savage Surgery Tue, 23 Aug 2016 06:01:26 +0000 Silver coating has demonstrated good antimicrobial activity and low toxicity. Silver-coated megaprostheses have been introduced in oncological musculoskeletal surgery considering the high rate of infection. We conducted a retrospective analysis on 68 cases of primary or metastatic bone tumors, affecting the proximal femur, treated between 2005 and 2016 with wide margins resection and tumor implants reconstruction. All patients were treated by the same surgeon, with antibiotic prophylaxis according to a standard protocol. In 55.9% of patients silver-coated hip hemiarthroplasty was implanted; in the remaining 44.1% uncoated megaprostheses were implanted. Patients were reevaluated recording the complications and focusing the analysis on infective complications. The average follow-up was 46.5 months. No patient has shown any sign of local or general silver toxicity. A SEM analysis was conducted on the 3-silver-coated hip hemiarthroplasty explanted confirming a severe degradation with a small amount of residual silver on the coating surface. Silver-coated hip prostheses have a lower rate of early infection than traditional implants but showed a reduction of antimicrobial activity for silver coating wear. We recommend using silver-coated prosthesis as primary implants for limb salvage surgery, in primary or metastatic bone tumors affecting the proximal femur, considering the absence of signs of toxicity and the lower rate of early infection. F. Donati, G. Di Giacomo, S. D’Adamio, A. Ziranu, S. Careri, MA. Rosa, and G. Maccauro Copyright © 2016 F. Donati et al. All rights reserved. Oral Biology, Oral Pathology, and Oral Treatments Sun, 21 Aug 2016 08:30:27 +0000 Samir Nammour, Toni Zeinoun, Kenji Yoshida, and Aldo Brugnera Junior Copyright © 2016 Samir Nammour et al. All rights reserved. A Preliminary In Vitro Study on the Efficacy of High-Power Photodynamic Therapy (HLLT): Comparison between Pulsed Diode Lasers and Superpulsed Diode Lasers and Impact of Hydrogen Peroxide with Controlled Stabilization Thu, 18 Aug 2016 16:29:07 +0000 Aim. In periodontology lasers have been suggested for the photodynamic therapy (PDT): such therapy can be defined as the inactivation of cells, microorganisms, or molecules induced by light and not by heat. The aim of this study was to evaluate results of PDT using a 980 nm diode laser (Wiser Doctor Smile, Lambda SPA, Italy) combined with hydrogen peroxide, comparing a pulsed diode laser (LI) activity to a high-frequency superpulsed diode laser (LII). Materials and Methods. Primary fibroblasts and keratinocytes cell lines, isolated from human dermis, were irradiated every 48 h for 10 days using LI and LII combined with SiOxyL+™ Solution (hydrogen peroxide (HP) stabilized with a glycerol phosphate complex). Two days after the last irradiation, the treated cultures were analyzed by flow cytofluorometry (FACS) and western blotting to quantify keratin 5 and keratin 8 with monoclonal antibodies reactive to cytokeratin 5 and cytokeratin 8. Antimicrobial activity was also evaluated. Results. Both experimental models show the superiority of LII against LI. In parallel, stabilized HP provided better results in the regeneration test in respect to common HP, while the biocidal activity remains comparable. Conclusion. The use of high-frequency lasers combined with stabilized hydrogen peroxide can provide optimal results for a substantial decrease of bacterial count combined with a maximal biostimulation induction of soft tissues and osteogenesis. Gianluigi Caccianiga, Marco Baldoni, Carlo Angelo Ghisalberti, and Alessio Paiusco Copyright © 2016 Gianluigi Caccianiga et al. All rights reserved. Wear Scar Similarities between Retrieved and Simulator-Tested Polyethylene TKR Components: An Artificial Neural Network Approach Sun, 14 Aug 2016 13:42:14 +0000 The aim of this study was to determine how representative wear scars of simulator-tested polyethylene (PE) inserts compare with retrieved PE inserts from total knee replacement (TKR). By means of a nonparametric self-organizing feature map (SOFM), wear scar images of 21 postmortem- and 54 revision-retrieved components were compared with six simulator-tested components that were tested either in displacement or in load control according to ISO protocols. The SOFM network was then trained with the wear scar images of postmortem-retrieved components since those are considered well-functioning at the time of retrieval. Based on this training process, eleven clusters were established, suggesting considerable variability among wear scars despite an uncomplicated loading history inside their hosts. The remaining components (revision-retrieved and simulator-tested) were then assigned to these established clusters. Six out of five simulator components were clustered together, suggesting that the network was able to identify similarities in loading history. However, the simulator-tested components ended up in a cluster at the fringe of the map containing only 10.8% of retrieved components. This may suggest that current ISO testing protocols were not fully representative of this TKR population, and protocols that better resemble patients’ gait after TKR containing activities other than walking may be warranted. Diego A. Orozco Villaseñor and Markus A. Wimmer Copyright © 2016 Diego A. Orozco Villaseñor and Markus A. Wimmer. All rights reserved. Effects of a Nonthermal Atmospheric Pressure Plasma Jet on Human Gingival Fibroblasts for Biomedical Application Thu, 11 Aug 2016 07:53:16 +0000 Nonthermal atmospheric pressure plasma jets (APPJ) have been developed and applied in biomedical research as a cancer treatment or bacterial sterilization. However, the drawback of APPJ on normal oral cells during plasma treatment and underlying cell death mechanisms have not been studied and clearly explained, although there is known to be an influence from reactive oxygen species (ROS). Hence, this study investigates whether and how a nonthermal atmospheric pressure air plasma jet kills human normal gingival cells using immortalized human gingival fibroblasts (hTERT-hNOF cells). In this study, a set of physicochemical or biological methods were used to illuminate the killing mechanisms. It was found that ROS were induced intracellularly without a breakdown of the cell wall and apoptosis was involved in cell death when an air APPJ treatment was performed on the cells directly without media; the air treatment only supported a detachment of the cells without increase of ROS. It was also revealed that a correlation between intracellular ROS concentration and cells viability existed. These results indicated that the direct air APPJ treatment possibly raises safety issue to normal tissue and thereby APPJ application in biomedical field needs more in vitro and in vivo study to optimize it. Jung-Hwan Lee and Kyoung-Nam Kim Copyright © 2016 Jung-Hwan Lee and Kyoung-Nam Kim. All rights reserved. Cytotoxicity and Initial Biocompatibility of Endodontic Biomaterials (MTA and Biodentine™) Used as Root-End Filling Materials Tue, 09 Aug 2016 14:09:21 +0000 Objective. The aim of this study was to evaluate the cytotoxicity and cellular adhesion of Mineral Trioxide Aggregate (MTA) and Biodentine (BD) on periodontal ligament fibroblasts (PDL). Methods. PDL cells were obtained from nonerupted third molars and cultured; MTS cellular profusion test was carried out in two groups: MTA and BD, with respective controls at different time periods. Also, the LIVE/DEAD assay was performed at 24 h. For evaluation of cellular adhesion, immunocytochemistry was conducted to discern the expression of Integrin β1 and Vinculin at 12 h and 24 h. Statistical analysis was performed by the Kruskal-Wallis and Mann-Whitney U tests. Results. MTA and BD exhibited living cells up to 7 days. More expressions of Integrin β1 and Vinculin were demonstrated in the control group, followed by BD and MTA, which also showed cellular loss and morphological changes. There was a significant difference in the experimental groups cultured for 5 and 7 days compared with the control, but there was no significant statistical difference between both cements. Conclusions. Neither material was cytotoxic during the time evaluated. There was an increase of cell adhesion through the expression of focal contacts observed in the case of BD, followed by MTA, but not significantly. Diana María Escobar-García, Eva Aguirre-López, Verónica Méndez-González, and Amaury Pozos-Guillén Copyright © 2016 Diana María Escobar-García et al. All rights reserved. Polydopamine-Assisted Surface Modification for Bone Biosubstitutes Tue, 09 Aug 2016 10:17:14 +0000 Polydopamine (PDA) prepared in the form of a layer of polymerized dopamine (DA) in a weak alkaline solution has been used as a versatile biomimetic surface modifier as well as a broadly used immobilizing macromolecule. This review mainly discusses the progress of biomaterial surface modification inspired by the participation of PDA in bone tissue engineering. A comparison between PDA-assisted coating techniques and traditional surface modification applied to bone tissue engineering is first presented. Secondly, the chemical composition and the underlying formation mechanism of PDA coating layer as a unique surface modifier are interpreted and discussed. Furthermore, several typical examples are provided to evidence the importance of PDA-assisted coating techniques in the construction of bone biosubstitutes and the improvement of material biocompatibility. Nowadays, the application of PDA as a superior surface modifier in multifunctional biomaterials is drawing tremendous interests in bone tissue scaffolds to promote the osteointegration for bone regeneration. Shishu Huang, Nuanyi Liang, Yang Hu, Xin Zhou, and Noureddine Abidi Copyright © 2016 Shishu Huang et al. All rights reserved. Histopathological Analysis of PEEK Wear Particle Effects on the Synovial Tissue of Patients Wed, 03 Aug 2016 06:18:53 +0000 Introduction. Increasing interest developed in the use of carbon-fiber-reinforced-poly-ether-ether-ketones (CFR-PEEK) as an alternative bearing material in knee arthroplasty. The effects of CFR-PEEK wear in in vitro and animal studies are controversially discussed, as there are no data available concerning human tissue. The aim of this study was to analyze human tissue containing CFR-PEEK as well as UHMWPE wear debris. The authors hypothesized no difference between the used biomaterials. Methods and Materials. In 10 patients during knee revision surgery of a rotating-hinge-knee-implant-design, synovial tissue samples were achieved (tibial inserts: UHMWPE; bushings and flanges: CFR-PEEK). One additional patient received revision surgery without any PEEK components as a control. The tissue was paraffin-embedded, sliced into 2 μm thick sections, and stained with hematoxylin and eosin in a standard process. A modified panoptical staining was also done. Results. A “wear-type” reaction was seen in the testing and the control group. In all samples, the UHMWPE particles were scattered in the tissue or incorporated in giant cells. CFR-PEEK particles were seen as conglomerates and only could be found next to vessels. CFR-PEEK particles showed no giant-cell reactions. In conclusion, the hypothesis has to be rejected. UHMWPE and PEEK showed a different scatter-behavior in human synovial tissue. A. C. Paulus, S. Haßelt, V. Jansson, A. Giurea, H. Neuhaus, T. M. Grupp, and S. Utzschneider Copyright © 2016 A. C. Paulus et al. All rights reserved. Three-Dimensional Assessment of Volumetric Changes in Sinuses Augmented with Two Different Bone Substitutes Tue, 19 Jul 2016 13:28:33 +0000 Introduction. The bone volume of the posterior maxilla may not be appropriate for implant placement, due to factors such as pneumatized maxillary sinus. The purpose of this study was to evaluate the percentage of graft volume reduction following sinus floor elevation (SFE), with either slow resorbable bone substitute only or a composite of slow and fast resorbable bone substitutes, using cone beam computed tomography (CBCT). Materials and Methods. In this retrospective study, CBCT scans of SFE procedures were evaluated to determine the volume of grafted sinus with either deproteinized bovine bone (DBB) or a 2 : 1 mixture of biphasic calcium sulfate (CS) and DBB, as a composite. The volumetric changes of sinus augmentations were measured 2 weeks (V-I) and 6 months (V-II) after operation. Results. Thirty-three patients were included in this study. The average percentage volume reduction was % and % for DBB and composite grafts, respectively. A significant graft volume reduction was observed between V-I and V-II for both groups (). The DBB group exhibited significantly less volume reduction than the composite group (). Conclusions. Augmented sinus volume may change before implant placement. DBB offers greater volume stability during healing than composite grafts. B. Alper Gultekin, Oguz Borahan, Ali Sirali, Z. Cuneyt Karabuda, and Eitan Mijiritsky Copyright © 2016 B. Alper Gultekin et al. All rights reserved. The Role of Resorbable Plate and Artificial Bone Substitute in Reconstruction of Large Orbital Floor Defect Tue, 19 Jul 2016 13:04:22 +0000 It is essential to reduce and reconstruct bony defects adequately in large orbital floor fracture and defect. Among many reconstructive methods, alloplastic materials have attracted attention because of their safety and ease of use. We have used resorbable plates combined with artificial bone substitutes in large orbital floor defect reconstructions and have evaluated their long-term reliability compared with porous polyethylene plate. A total of 147 patients with traumatic orbital floor fracture were included in the study. Surgical results were evaluated by clinical evaluations, exophthalmometry, and computed tomography at least 12 months postoperatively. Both orbital floor height discrepancy and orbital volume change were calculated and compared with preoperative CT findings. The average volume discrepancy and vertical height discrepancies were not different between two groups. Also, exophthalmometric measurements were not significantly different between the two groups. No significant postoperative complication including permanent diplopia, proptosis, and enophthalmos was noted. Use of a resorbable plate with an artificial bone substitute to repair orbital floor defects larger than 2.5 cm2 in size yielded long-lasting, effective reconstruction without significant complications. We therefore propose our approach as an effective alternative method for large orbital floor reconstructions. Ho Kwon, Ho Jun Kim, Bommie F. Seo, Yeon Jin Jeong, Sung-No Jung, and Hyung-Sup Shim Copyright © 2016 Ho Kwon et al. All rights reserved. Soft Tissue Augmentation Techniques in Implants Placed and Provisionalized Immediately: A Systematic Review Tue, 19 Jul 2016 12:18:05 +0000 The aim of this study was to evaluate the effectiveness of techniques for soft tissue augmentation in the placement of immediate implants with and without provisionalization and to assess the quality of the reports in the literature. Randomized clinical trials, prospective clinical trials, and case series were included in this review. Clinical questions were formulated and organised according to the PICOS strategy. An electronic search was performed in PubMed, Cochrane Central Register of Controlled Trials, Scopus, and ISI Web up until June 2016. Interexaminer agreement on eligibility (; ) and quality (; ) was high. Methodological approaches were assessed using criteria based on design related forms designed by the Dutch Cochrane Collaboration. Finally, 14 papers were identified. In two studies, the implant survival was 90%; for the rest of the studies it was 100%. All studies reported favourable aesthetic, biological, and radiographic outcomes. Surgical and biomechanical complications of this technique were not relevant. This technique effectively compensates for the expected loss of volume of the oral soft tissues and maintains high success rates with good aesthetic results over time. Rosa Rojo, Juan Carlos Prados-Frutos, Ángel Manchón, Jesús Rodríguez-Molinero, Gilberto Sammartino, José Luis Calvo Guirado, and Rafael Gómez-de Diego Copyright © 2016 Rosa Rojo et al. All rights reserved. In Vitro Bioactivity Study of RGD-Coated Titanium Alloy Prothesis for Revision Total Hip Arthroplasty Thu, 14 Jul 2016 07:42:51 +0000 Total hip arthroplasty (THA) is a common procedure for the treatment of end-stage hip joint disease, and the demand for revision THA will double by 2026. Ti6Al4V (Titanium, 6% Aluminum, and 4% Vanadium) is a kind of alloy commonly used to make hip prothesis. To promote the osseointegration between the prothesis and host bone is very important for the revision THA. The peptide Arg-Gly-Asp (RGD) could increase cell attachment and has been used in the vascular tissue engineering. In this study, we combined the RGD with Ti6Al4V alloy using the covalent cross-linking method to fabricate the functional Ti6Al4V alloy (FTA). The distribution of RGD oligopeptide on the FTA was even and homogeneous. The FTA scaffolds could promote mouse osteoblasts adhesion and spreading. Furthermore, the result of RT-qPCR indicated that the FTA scaffolds were more beneficial to osteogenesis, which may be due to the improvement of osteoblast adhesion by the RGD oligopeptide coated on FTA. Overall, the FTA scaffolds developed herein pave the road for designing and building more efficient prothesis for osseointegration between the host bone and prothesis in revision THA. Zhentao Man, Dan Sha, Shui Sun, Tao Li, Bin Li, Guang Yang, Laibo Zhang, Changshun Wu, Peng Jiang, Xiaojuan Han, and Wei Li Copyright © 2016 Zhentao Man et al. All rights reserved. Evaluation of Implant Collar Surfaces for Marginal Bone Loss: A Systematic Review and Meta-Analysis Thu, 14 Jul 2016 07:01:56 +0000 Background. It is important to understand the influence of different collar designs on peri-implant marginal bone loss, especially in the critical area. Objectives. The purpose of the present systematic review and meta-analysis was to compare dental implants with different collar surfaces, evaluating marginal bone loss and survival rates of implants. Methods. Eligibility criteria included clinical human studies, randomized controlled trials, and prospective and retrospective studies, which evaluated dental implants with different collar surface in the same study. Results. Twelve articles were included, with a total of 492 machined, 319 rough-surfaced, and 352 rough-surfaced microthreaded neck implants. There was less marginal bone loss at implants with rough-surfaced and rough-surfaced microthreaded neck than at machined-neck implants (difference in means: 0.321, 95% CI: 0.149 to 0.493; ). Conclusion. Rough and rough-surfaced microthreaded implants are considered a predictable treatment for preserving early marginal bone loss. Roodabeh Koodaryan and Ali Hafezeqoran Copyright © 2016 Roodabeh Koodaryan and Ali Hafezeqoran. All rights reserved. Soft Tissue Augmentation with Autologous Platelet Gel and β-TCP: A Histologic and Histometric Study in Mice Tue, 12 Jul 2016 13:59:49 +0000 Background. Facial aging is a dynamic process involving both soft tissue and bony structures. Skin atrophy, with loss of tone, elasticity, and distribution of facial fat, coupled with gravity and muscle activity, leads to wrinkling and folds. Purpose. The aim of the study was to evaluate microporous tricalcium phosphate (β-TCP) and autologous platelet gel (APG) mix in mice for oral and maxillofacial soft tissue augmentation. The hypothesis was that β-TCP added with APG was able to increase the biostimulating effect on fibroblasts and quicken resorption. Materials and Methods. Ten female, 6–8-week-old black-haired mice were selected. β-TCP/APG gel was injected into one cheek; the other was used as control. The animals were sacrificed at 8 weeks and histologically evaluated. Results. The new fibroblast was intensively stained with acid fuchsin and presented in contact with β-TCP. At higher magnification, actively secreting fibroblasts were observed at the periphery of β-TCP with a well differentiated fibroblast cell line and blood vessels. Acid fuchsin stained cutaneous structures in pink: no epidermal/dermal alterations or pathological inflammatory infiltrates were detected. The margins of β-TCP granules were clear and not diffused near tissues. Conclusion. APG with β-TCP preserves skin morphology, without immune response, with an excellent tolerability and is a promising scaffold for cells and biomaterial for soft tissue augmentation. Antonio Scarano, Maurizio Ceccarelli, Massimiliano Marchetti, Adriano Piattelli, and Carmen Mortellaro Copyright © 2016 Antonio Scarano et al. All rights reserved. Impact of Dental Implant Surface Modifications on Osseointegration Mon, 11 Jul 2016 07:13:01 +0000 Objective. The aim of this paper is to review different surface modifications of dental implants and their effect on osseointegration. Common marketed as well as experimental surface modifications are discussed. Discussion. The major challenge for contemporary dental implantologists is to provide oral rehabilitation to patients with healthy bone conditions asking for rapid loading protocols or to patients with quantitatively or qualitatively compromised bone. These charging conditions require advances in implant surface design. The elucidation of bone healing physiology has driven investigators to engineer implant surfaces that closely mimic natural bone characteristics. This paper provides a comprehensive overview of surface modifications that beneficially alter the topography, hydrophilicity, and outer coating of dental implants in order to enhance osseointegration in healthy as well as in compromised bone. In the first part, this paper discusses dental implants that have been successfully used for a number of years focusing on sandblasting, acid-etching, and hydrophilic surface textures. Hereafter, new techniques like Discrete Crystalline Deposition, laser ablation, and surface coatings with proteins, drugs, or growth factors are presented. Conclusion. Major advancements have been made in developing novel surfaces of dental implants. These innovations set the stage for rehabilitating patients with high success and predictable survival rates even in challenging conditions. Ralf Smeets, Bernd Stadlinger, Frank Schwarz, Benedicta Beck-Broichsitter, Ole Jung, Clarissa Precht, Frank Kloss, Alexander Gröbe, Max Heiland, and Tobias Ebker Copyright © 2016 Ralf Smeets et al. All rights reserved. Laser Application in Dentistry: Irradiation Effects of Nd:YAG 1064 nm and Diode 810 nm and 980 nm in Infected Root Canals—A Literature Overview Mon, 04 Jul 2016 11:28:07 +0000 Objective. In endodontics, Nd:YAG laser (1064 nm) and diode laser (810 nm and 980 nm) devices are used to remove bacteria in infected teeth. A literature review was elaborated to compare and evaluate the advantages and disadvantages of using these lasers. Methods. Using combined search terms, eligible articles were retrieved from PubMed and printed journals. The initial search yielded 40 titles and 27 articles were assigned to full-text analysis. The studies were classified based upon laser source, laser energy level, duration/similarity of application, and initial and final bacterial count at a minimum of 20 prepared root canals. Part of the analysis was only reduced microorganisms and mechanically treated root canals upon preparation size of ISO 30. All studies were compared to evaluate the most favorable laser device for best results in endodontic therapy. Results. A total of 22 eligible studies were found regarding Nd:YAG laser 1064 nm. Four studies fulfilled all demanded criteria. Seven studies referring to the diode laser 980 nm were examined, although only one fulfilled all criteria. Eleven studies were found regarding the diode laser 810 nm, although only one study fulfilled all necessary criteria. Conclusions. Laser therapy is effective in endodontics, although a comparison of efficiency between the laser devices is not possible at present due to different study designs, materials, and equipment. Yves Saydjari, Thorsten Kuypers, and Norbert Gutknecht Copyright © 2016 Yves Saydjari et al. All rights reserved. Transmission of Curing Light through Moist, Air-Dried, and EDTA Treated Dentine and Enamel Thu, 30 Jun 2016 10:29:15 +0000 Objective. This study measured light transmission through enamel and dentin and the effect of exposed dentinal tubules to light propagation. Methods. Light attenuation through enamel and dentin layers of various thicknesses (1 mm, 2 mm, 3 mm, and 4 mm) was measured using specimens that were (1) moist and (2) air-dried (). Measurements were repeated after the specimens were treated with EDTA. Specimens were transilluminated with a light curing unit (maximum power output 1869 mW/cm2), and the mean irradiance power of transmitting light was measured. The transmission of light through teeth was studied using 10 extracted intact human incisors and premolars. Results. Transmitted light irradiance through 1 mm thick moist discs was 500 mW/cm2 for enamel and 398 mW/cm2 for dentin (). The increase of the specimen thickness decreased light transmission in all groups (), and moist specimens attenuated light less than air-dried specimens in all thicknesses (). EDTA treatment increased light transmission from 398 mW/cm2 to 439 mW/cm2 (1 mm dentin specimen thickness) (). Light transmission through intact premolar was 6.2 mW/cm2 (average thickness 8.2 mm) and through incisor was 37.6 mW/cm2 (average thickness 5.6 mm). Conclusion. Light transmission through enamel is greater than that through dentin, probably reflecting differences in refractive indices and extinction coefficients. Light transmission through enamel, dentin, and extracted teeth seemed to follow Beer-Lambert’s law. E. Uusitalo, J. Varrela, L. Lassila, and P. K. Vallittu Copyright © 2016 E. Uusitalo et al. All rights reserved. Fretting and Corrosion in Modular Shoulder Arthroplasty: A Retrieval Analysis Tue, 28 Jun 2016 16:00:28 +0000 Tribocorrosion in taper junctions of retrieved anatomic shoulder arthroplasty implants was evaluated. A comparison of the tribocorrosion between cobalt-chromium and titanium alloy stems was conducted and the observations were correlated with the individual’s clinical data. Adverse effects caused by metal debris and subsequent elevated serum metal ion levels are frequently reported in total hip arthroplasty. In total shoulder arthroplasty, to date only a small number of retrieval analyses are available and even fewer address the issue of tribocorrosion at the taper junctions. A total of 36 retrieved hemiarthroplasties and total shoulder arthroplasties were assessed using the modified Goldberg score. The prevalence of fretting and corrosion was confirmed in this cohort. Titanium stems seem to be more susceptible to damage caused by tribocorrosion than cobalt-chromium stems. Furthermore, stemless designs offered less tribocorrosion at the taper junction than stemmed designs. A weak correlation between time to revision and increased levels of tribocorrosion was seen. Whether or not tribocorrosion can lead to adverse clinical reactions and causes failure of shoulder arthroplasties remains to be examined. Johannes A. Eckert, Ulrike Mueller, Sebastian Jaeger, Benjamin Panzram, and J. Philippe Kretzer Copyright © 2016 Johannes A. Eckert et al. All rights reserved. MicroRNAs as Salivary Markers for Periodontal Diseases: A New Diagnostic Approach? Mon, 27 Jun 2016 12:07:52 +0000 The aim of this review is to discuss current findings regarding the roles of miRNAs in periodontal diseases and the potential use of saliva as a diagnostic medium for corresponding miRNA investigations. For periodontal disease, investigations have been restricted to tissue samples and five miRNAs, that is, miR-142-3p, miR-146a, miR-155, miR-203, and miR-223, were repeatedly validated in vivo and in vitro by different validation methods. Particularly noticeable are the small sample sizes, different internal controls, and different case definitions of periodontitis in in vivo studies. Beside of that, the validated miRNAs are associated with inflammation and therefore with various diseases. Furthermore, several studies successfully explored the use of salivary miRNA species for the diagnosis of oral cancer. Different cancer types were investigated and heterogeneous methodology was used; moreover, no overlap of results was found. In conclusion, five miRNAs have consistently been reported for periodontitis; however, their disease specificity, detectability, and expression in saliva and their importance as noninvasive markers are questionable. In principle, a salivary miRNA diagnostic method seems feasible. However, standardized criteria and protocols for preanalytics, measurements, and analysis should be established to obtain comparable results across different studies. Gerhard Schmalz, Simin Li, Ralph Burkhardt, Sven Rinke, Felix Krause, Rainer Haak, and Dirk Ziebolz Copyright © 2016 Gerhard Schmalz et al. All rights reserved. A Comparative Study of Microleakage on Dental Surfaces Bonded with Three Self-Etch Adhesive Systems Treated with the Er:YAG Laser and Bur Wed, 22 Jun 2016 14:24:41 +0000 Aim. This study sought to compare the microleakage of three adhesive systems in the context of Erbium-YAG laser and diamond bur cavity procedures. Cavities were restored with composite resin. Materials and Methods. Standardized Class V cavities were performed in 72 extracted human teeth by means of diamond burs or Er-YAG laser. The samples were randomly divided into six groups of 12, testing three adhesive systems (Clearfil s3 Bond Plus, Xeno® Select, and Futurabond U) for each method used. Cavities were restored with composite resin before thermocycling (methylene blue 2%, 24 h). The slices were prepared using a microtome. Optical microscope photography was employed to measure the penetration. Results. No statistically significant differences in microleakage were found in the use of bur or laser, nor between adhesive systems. Only statistically significant values were observed comparing enamel with cervical walls (). Conclusion. It can be concluded that the Er:YAG laser is as efficient as diamond bur concerning microleakage values in adhesive restoration procedures, thus constituting an alternative tool for tooth preparation. Youssef Sanhadji El Haddar, Sibel Cetik, Babak Bahrami, and Ramin Atash Copyright © 2016 Youssef Sanhadji El Haddar et al. All rights reserved. Development of Alginate Microspheres Containing Chuanxiong for Oral Administration to Adult Zebrafish Wed, 15 Jun 2016 07:03:50 +0000 Oral administration of Traditional Chinese Medicine (TCM) by patients is the common way to treat health problems. Zebrafish emerges as an excellent animal model for the pharmacology investigation. However, the oral delivery system of TCM in zebrafish has not been established so far. This issue was addressed by development of alginate microparticles for oral delivery of chuanxiong, a TCM that displays antifibrotic and antiproliferative effects on hepatocytes. The delivery microparticles were prepared from gelification of alginate containing various levels of chuanxiong. The chuanxiong-encapsulated alginate microparticles were characterized for their solubility, structure, encapsulation efficiency, the cargo release profile, and digestion in gastrointestinal tract of zebrafish. Encapsulation of chuanxiong resulted in more compact structure and the smaller size of microparticles. The release rate of chuanxiong increased for alginate microparticles carrying more chuanxiong in simulated intestinal fluid. This remarkable feature ensures the controlled release of encapsulated cargos in the gastrointestinal tract of zebrafish. Moreover, chuanxiong-loaded alginate microparticles were moved to the end of gastrointestinal tract after oral administration for 6 hr and excreted from the body after 16 hr. Therefore, our developed method for oral administration of TCM in zebrafish is useful for easy and rapid evaluation of the drug effect on disease. Li-Jen Lin, Chung-Jen Chiang, Yun-Peng Chao, Shulhn-Der Wang, Yu-Ting Chiou, Han-Yu Wang, and Shung-Te Kao Copyright © 2016 Li-Jen Lin et al. All rights reserved. Influence of Trabecular Bone on Peri-Implant Stress and Strain Based on Micro-CT Finite Element Modeling of Beagle Dog Tue, 14 Jun 2016 11:01:10 +0000 The objective of this investigation is to analyze the influence of trabecular microstructure modeling on the biomechanical distribution of the implant-bone interface. Two three-dimensional finite element mandible models, one with trabecular microstructure (a refined model) and one with macrostructure (a simplified model), were built. The values of equivalent stress at the implant-bone interface in the refined model increased compared with those of the simplified model and strain on the contrary. The distributions of stress and strain were more uniform in the refined model of trabecular microstructure, in which stress and strain were mainly concentrated in trabecular bone. It was concluded that simulation of trabecular bone microstructure had a significant effect on the distribution of stress and strain at the implant-bone interface. These results suggest that trabecular structures could disperse stress and strain and serve as load buffers. Sheng-hui Liao, Xing-hao Zhu, Jing Xie, Vikesh Kumar Sohodeb, and Xi Ding Copyright © 2016 Sheng-hui Liao et al. All rights reserved. Long-Term Fracture Resistance of Simulated Immature Teeth Filled with Various Calcium Silicate-Based Materials Mon, 13 Jun 2016 11:55:09 +0000 Objective. The aim of this in vitro study was to evaluate the long-term fracture resistance of simulated human immature permanent teeth filled with BioAggregate™ (BA), mineral trioxide aggregate (MTA), and EndoSequence® Root Repair Material (ERRM). Material and Methods. 40 teeth, simulated to average root length of  mm (Cvek’s stage 3), were included in the study. The teeth were randomly divided into four groups: Group 1: DiaRoot® BA, Group 2: MTA-Plus™ (MTA-P), Group 3: MTA-Angelus (MTA-A), and Group 4: ERRM. The root canal filling materials were applied according to the manufacturers’ instructions. After 24 months of incubation, the roots of the teeth were embedded in acrylic blocks and subjected to fracture testing. The resultant data were analyzed statistically by Kruskal-Wallis and Mann-Whitney tests. Results. Mean (±SD) failure loads (MPa) were for BA, for MTA-P, for MTA-A, and for ERRM groups. BA group exhibited the highest and MTA-A group showed the lowest resistance to fracture. Significant differences in fracture resistance were found between the groups of BA and MTA-A (), MTA-P and MTA-A (), and ERRM and MTA-A (). Conclusion. Within the limitations of this study, data suggests that BA-filled immature teeth demonstrate higher fracture resistance than other groups at 24 months appearing to be the most promising material tested. Yeliz Guven, Elif Bahar Tuna, M. Emir Dincol, Emre Ozel, Bulent Yilmaz, and Oya Aktoren Copyright © 2016 Yeliz Guven et al. All rights reserved. Effect of Surface Treatment on Shear Bond Strength between Resin Cement and Ce-TZP/Al2O3 Mon, 13 Jun 2016 08:24:08 +0000 Purpose. Although several studies evaluating the mechanical properties of Ce-TZP/Al2O3 have been published, to date, no study has been published investigating the bonding protocol between Ce-TZP/Al2O3 and resin cement. The aim of this study was to evaluate the shear bond strength to air-abraded Ce-TZP/Al2O3 when primers and two different cement types were used. Materials and Methods. Two types of zirconia (Y-TZP and Ce-TZP/Al2O3) specimens were further divided into four subgroups according to primer application and the cement used. Shear bond strength was measured after water storage for 3 days or 5,000 times thermocycling for artificial aging. Results. The Y-TZP block showed significantly higher shear bond strength than the Ce-TZP/Al2O3 block generally. Primer application promoted high bond strength and less effect on bond strength reduction after thermocycling, regardless of the type of cement, zirconia block, or aging time. Conclusions. Depending on the type of the primer or resin cement used after air-abrasion, different wettability of the zirconia surface can be observed. Application of primer affected the values of shear bond strength after the thermocycling procedure. In the case of using the same bonding protocol, Y-TZP could obtain significantly higher bond strength compared with Ce-TZP/Al2O3. Jong-Eun Kim, Jee-Hwan Kim, June-Sung Shim, Byoung-Duck Roh, and Yooseok Shin Copyright © 2016 Jong-Eun Kim et al. All rights reserved. Clinical, Radiographic and Microbiological Evaluation of High Level Laser Therapy, a New Photodynamic Therapy Protocol, in Peri-Implantitis Treatment; a Pilot Experience Thu, 09 Jun 2016 14:11:25 +0000 Aim. Endosseous implants are widely used to replace missing teeth but mucositis and peri-implantitis are the most frequent long-term complications related with dental implants. Removing all bacterial deposits on contaminated implant surface is very difficult due to implant surface morphology. The aim of this study was to evaluate the bactericidal potential of photodynamic therapy by using a new high level laser irradiation protocol associated with hydrogen peroxide in peri-implantitis. Materials and Methods. 10 patients affected by peri-implantitis were selected for this study. Medical history, photographic documentation, periodontal examination, and periapical radiographs were collected at baseline and 6 months after surgery. Microbiological analysis was performed with PCR Real Time. Each patient underwent nonsurgical periodontal therapy and surgery combined with photodynamic therapy according to High Level Laser Therapy protocol. Results. All peri-implant pockets were treated successfully, without having any complication and not showing significant differences in results. All clinical parameters showed an improvement, with a decrease of Plaque Index (average decrease of 65%, range 23–86%), bleeding on probing (average decrease of 66%, range 26–80%), and probing depth (average decrease of 1,6 mm, range 0,46–2,6 mm). Periapical radiographs at 6 months after surgery showed a complete radiographic filling of peri-implant defect around implants treated. Results showed a decrease of total bacterial count and of all bacterial species, except for Eikenella corrodens, 6 months after surgery. Conclusion. Photodynamic therapy using HLLT appears to be a good adjunct to surgical treatment of peri-implantitis. Gianluigi Caccianiga, Gerard Rey, Marco Baldoni, and Alessio Paiusco Copyright © 2016 Gianluigi Caccianiga et al. All rights reserved. A Long-Acting BMP-2 Release System Based on Poly(3-hydroxybutyrate) Nanoparticles Modified by Amphiphilic Phospholipid for Osteogenic Differentiation Thu, 09 Jun 2016 12:24:59 +0000 We explored a novel poly(3-hydroxybutyrate) (PHB) nanoparticle loaded with hydrophilic recombinant human BMP-2 with amphiphilic phospholipid (BPC-PHB NP) for a rapid-acting and long-acting delivery system of BMP-2 for osteogenic differentiation. The BPC-PHB NPs were prepared by a solvent evaporation method and showed a spherical particle with a mean particle size of 253.4 nm, mean zeta potential of −22.42 mV, and high entrapment efficiency of 77.18%, respectively. For BPC-PHB NPs, a short initial burst release of BMP-2 from NPs in 24 h was found and it has steadily risen to reach about 80% in 20 days for in vitro test. BPC-PHB NPs significantly reduced the burst release of BMP-2, as compared to that of PHB NPs loading BMP-2 without PL (B-PHB NPs). BPC-PHB NPs maintained the content of BMP-2 for a long-term osteogenic differentiation. The OCT-1 cells with BPC-PHB NPs have high ALP activity in comparison with others. The gene markers for osteogenic differentiation were significantly upregulated for sample with BPC-PHB NPs, implying that BPC-PHB NPs can be used as a rapid-acting and long-acting BMP-2 delivery system for osteogenic differentiation. Xiaochun Peng, Yunsu Chen, Yamin Li, Yiming Wang, and Xianlong Zhang Copyright © 2016 Xiaochun Peng et al. All rights reserved. Safety Irradiation Parameters of Nd:YAP Laser Beam for Endodontic Treatments: An In Vitro Study Wed, 08 Jun 2016 12:25:21 +0000 Objective. Nd:YAP laser has several potentialities of clinical applications in endodontics. The aim of our study is to determine the safety range of irradiation parameters during endodontic application of Nd:YAP laser that can be used without damaging and overheating the periodontal tissue. Material and Methods. Twenty-seven caries-free single-rooted extracted human teeth were used. Crowns were sectioned to obtain 11 mm root canal length. Temperature increases at root surfaces were measured by a thermocouple during Nd:YAP laser irradiation of root canals at different energy densities. Canal irradiation was accomplished with a circular and retrograde movement from the apex until the cervical part of the canal during 10 seconds with an axial speed of 1 mm/s. Each irradiation was done in a canal irrigated continuously with 2.25% NaOCl solution. Results. Periodontal temperature increase depends on the value of energy density. Means and standard deviations of temperature increases at root surfaces were below 10°C (safe threshold level) when the average energy densities delivered per second were equal to or below 4981 J/cm2 and 9554 J/cm2, respectively, for irradiations using a fiber diameter of 320 μm and 200 μm. Conclusions. Within the limitations of this study and under specific irradiation conditions, Nd:YAP laser beam may be considered harmless for periodontal tissues during endodontic applications. A. Namour, S. Geerts, T. Zeinoun, R. De Moor, and S. Nammour Copyright © 2016 A. Namour et al. All rights reserved. Soft Tissue Response to Titanium Abutments with Different Surface Treatment: Preliminary Histologic Report of a Randomized Controlled Trial Mon, 06 Jun 2016 12:45:12 +0000 The aim of this preliminary prospective RCT was to histologically evaluate peri-implant soft tissues around titanium abutments treated using different cleaning methods. Sixteen patients were randomized into three groups: laboratory customized abutments underwent Plasma of Argon treatment (Plasma Group), laboratory customized abutments underwent cleaning by steam (Steam Group), and abutments were used as they came from industry (Control Group). Seven days after the second surgery, soft tissues around abutments were harvested. Samples were histologically analyzed. Soft tissues surrounding Plasma Group abutments predominantly showed diffuse chronic infiltrate, almost no acute infiltrate, with presence of few polymorphonuclear neutrophil granulocytes, and a diffuse presence of collagenization bands. Similarly, in Steam Group, the histological analysis showed a high variability of inflammatory expression factors. Tissues harvested from Control Group showed presence of few neutrophil granulocytes, moderate presence of lymphocytes, and diffuse collagenization bands in some sections, while they showed absence of acute infiltrate in 40% of sections. However, no statistical difference was found among the tested groups for each parameter (). Within the limit of the present study, results showed no statistically significant difference concerning inflammation and healing tendency between test and control groups. Luigi Canullo, Jan Friedrich Dehner, David Penarrocha, Vittorio Checchi, Annalisa Mazzoni, and Lorenzo Breschi Copyright © 2016 Luigi Canullo et al. All rights reserved. Fibronectin-Grafted Titanium Dental Implants: An In Vivo Study Mon, 06 Jun 2016 12:35:02 +0000 Modification of the physiochemical properties of titanium surfaces using glow discharge plasma (GDP) and fibronectin coating has been shown to enhance the surface hydrophilicity, surface roughness, cell adhesion, migration, and proliferation. This in vivo study aimed to evaluate the bone integration efficacy of a biologically modified implant surface. Two different surface-modified implants (Ar-GDP and GDP-fib) were placed in the mandibular premolar area of six beagle dogs for 2–8 weeks. Three techniques [histologic evaluation, resonance frequency analysis (RFA), and microcomputed tomography (micro-CT) evaluation] were used to detect the implant stability and bone-implant contact. The implant stability quotient values of GDP-fib implants were significantly greater than the Ar-GDP implants at 2 and 4 weeks (). The bone volume/total volume ratio of GDP-fib implants was greater than the Ar-GDP implants in micro-CT evaluation. A high positive correlation was observed between RFA and micro-CT measurements. At 2 weeks, osteoblasts were seen to line the implant surface, and multinuclear osteoclasts could be seen on the surface of old parent bone. After 8 weeks, a majority of the space in the wound chamber appeared to be replaced by bone. Enhancement of the stability of biologically modified implants was proved by the results of RFA, micro-CT, and histological analysis. This enhanced stability may help fasten treatment and be clinically beneficial. Yu-Chi Chang, Kuo-Ning Ho, Sheng-Wei Feng, Haw-Ming Huang, Chia-Hsun Chang, Che-Tong Lin, Nai-Chia Teng, Yu Hwa Pan, and Wei-Jen Chang Copyright © 2016 Yu-Chi Chang et al. All rights reserved. The Influence of Irradiation Time and Layer Thickness on Elution of Triethylene Glycol Dimethacrylate from SDR® Bulk-Fill Composite Mon, 06 Jun 2016 11:09:17 +0000 Objective. This study aimed to evaluate triethylene glycol dimethacrylate (TEGDMA) elution from SDR bulk-fill composite. Methods. Three groups of samples were prepared, including samples polymerized in a 4 mm layer for 20 s, in a 4 mm layer for 40 s, and in a 2 mm layer for 20 s. Elution of TEGDMA into 100% ethanol, a 75% ethanol/water solution, and distilled water was studied. The TEGDMA concentration was measured using HPLC. Results. The TEGDMA concentration decreased in the following order: 100% ethanol > 75% ethanol > distilled water. Doubling the energy delivered to the 4 mm thick sample caused decrease () in TEGDMA elution to distilled water. In ethanol solutions, the energy increase had no influence on TEGDMA elution. Decreasing the sample thickness resulted in decrease () in TEGDMA elution for all the solutions. Conclusions. The concentration of eluted TEGDMA and the elution time were both strongly affected by the hydrophobicity of the solvent. Doubling the energy delivered to the 4 mm thick sample did not decrease the elution of TEGDMA but did decrease the amount of the monomer available to less aggressive solvents. Elution of TEGDMA was also correlated with the exposed sample surface area. Clinical Relevance. Decreasing the SDR layer thickness decreases TEGDMA elution. Ryta Łagocka, Katarzyna Jakubowska, Dariusz Chlubek, and Jadwiga Buczkowska-Radlińska Copyright © 2016 Ryta Łagocka et al. All rights reserved. Pilot Study of Laser Doppler Measurement of Flow Variability in the Microcirculation of the Palatal Mucosa Wed, 01 Jun 2016 12:49:01 +0000 Background. Histopathological alterations can arise when the denture-supporting mucosa experiences microbial and mechanical stress through the denture base and diagnosis of these diseases usually follows microvascular changes. Microcirculation measurement could allow for detection of such dysfunction and aid in the early diagnosis of palatal mucosa pathologies. Materials and Methods. We tested the sensitivity of laser Doppler for measuring the microcirculation of the palatal mucosa, assessing the median raphe (MR), Schroeder area (SA), and retroincisive papilla (RP). A Doppler PeriFlux 5000 System, containing a laser diode, was used. 54 healthy participants were recruited. We compare the measurements of PU (perfusion unit) using ANOVA test. Results. The numerical values for palatal mucosa blood flow differed significantly among the anatomical areas (). The mean value of Schroeder area was 92.6 (SD: 38.4) and was significantly higher than the retroincisive papilla (51.9) (SD: 20.2) (), which in turn was higher than that of median raphe (31.9) (SD: 24.2) (). Conclusion. Schroeder area appeared to have the greatest sensitivity, and vascular flow variability among individuals was also greatest in this region. We suggest that analysis of blood stream modification with laser Doppler of the palatal mucosa can help to detect onset signs of pathological alterations. Pierre Le Bars, Gaston Niagha, Ayepa Alain Kouadio, Julien Demoersman, Elisabeth Roy, Valérie Armengol, and Assem Soueidan Copyright © 2016 Pierre Le Bars et al. All rights reserved. Bone Regeneration in Iliac Crestal Defects: An Experimental Study on Sheep Mon, 30 May 2016 12:33:30 +0000 Background. Oral rehabilitation of partially fully edentulous patients with dental implants has become a routine procedure in clinical practice. In a site with a lack of bone GBR is a surgical procedure that provides an augmentation in terms of volume for the insertion of dental implants. Materials and Methods. In the iliac crest of six sheep 4 defects were created where an implant was inserted, three of them with different biomaterials and a control site. All animals were sacrificed after a 4-month healing period. All specimens were processed and analyzed with histomorphometry. Statistical evaluation was done to evaluate percentage of bone defect filled by new bone. Results. All experimental groups showed an increase of the new bone. Higher and highly statistically significant differences were found in the percentages of bone defect filled by new bone in group filled with corticocancellous 250–1000 microns particulate porcine bone mix. Conclusions. This study demonstrates that particulate porcine bone mix and porcine corticocancellous collagenate prehydrated bone mix when used as scaffold are able to induce bone regeneration. Moreover, these data suggest that these biomaterials have higher biocompatibility and are capable of inducing faster and greater bone formation. Antonio Scarano, Felice Lorusso, Lorenzo Ravera, Carmen Mortellaro, and Adriano Piattelli Copyright © 2016 Antonio Scarano et al. All rights reserved. The Relevance of the Use of Radiographic Planning in Order to Avoid Complications in Mandibular Implantology: A Retrospective Study Thu, 12 May 2016 17:27:43 +0000 The aim of this retrospective radiological study was to evaluate the variability of the mandibular anatomy in the presence and absence of teeth and to consider how it could influence implant planning. 187 mandibular CT DentaScans were selected from our department archive according to the inclusion criteria. The axial height, vertical height, angulation of the bone crest, and the bone available for ideal implant placement were measured. The analysis of the data shows that the mandible contour presents a constant degree of angulation. The variation of angulation in the absence of teeth was statistically significant only in the region between the canine and the first premolar and in that between the second premolar and the first molar. The difference between the crest height and the available distance to place the implant was greater in the region of the second molar while in the other regions the implant planning was made complex by postextraction resorption. Alveolar bone resorption after tooth loss can be considered as a risk factor for lingual cortical perforation during the insertion of an implant. To avoid potential intra/postoperative complications, 3D radiographic examination is recommended in order to study the mandibular anatomy and identify the risk areas. Gilberto Sammartino, Juan Carlos Prados-Frutos, Francesco Riccitiello, Pietro Felice, Vincenzo Cerone, Roberta Gasparro, and Hom-Lay Wang Copyright © 2016 Gilberto Sammartino et al. All rights reserved. A Comparison of Conventional Collagen Sponge and Collagen-Gelatin Sponge in Wound Healing Wed, 27 Apr 2016 14:25:39 +0000 The objective of this study was to compare the effectiveness of the collagen-gelatin sponge (CGS) with that of the collagen sponge (CS) in dermis-like tissue regeneration. CGS, which achieves the sustained release of basic fibroblast growth factor (bFGF), is a promising material in wound healing. In the present study, we evaluated and compared CGSs and conventional CSs. We prepared 8 mm full-thickness skin defects on the backs of rats. Either CGSs or CSs were impregnated with normal saline solution (NSS) or 7 μg/cm2 of bFGF solution and implanted into the defects. At 1 and 2 weeks after implantation, tissue specimens were obtained from the rats of each group (, total ). The wound area, neoepithelial length, dermis-like tissue area, and the number and area of capillaries were evaluated at 1 and 2 weeks after implantation. There were no significant differences in the CGS without bFGF and CS groups. Significant improvements were observed in the neoepithelial length, the dermis-like tissue area, and the number of newly formed capillaries in the group of rats that received CGSs impregnated with bFGF. The effects on epithelialization, granulation, and vascularization of wound healing demonstrated that, as a scaffold, CGSs are equal or superior to conventional CSs. Chizuru Jinno, Naoki Morimoto, Ran Ito, Michiharu Sakamoto, Shuichi Ogino, Tsuguyoshi Taira, and Shigehiko Suzuki Copyright © 2016 Chizuru Jinno et al. All rights reserved. Preparation, Characterization, and Insecticidal Activity of Avermectin-Grafted-Carboxymethyl Chitosan Sun, 24 Apr 2016 09:10:23 +0000 Avermectin-grafted-N,O-carboxymethyl chitosan (NOCC) derivative was obtained by esterification reaction using dicyclohexylcarbodiimide (DCC) as dehydrating agent and 4-methylaminopyridine as catalyst. The structures of the conjugate were confirmed by FT-IR, 1H NMR, and XRD. Insecticidal activities against armyworms, carmine spider mites, black bean aphids, and brown plant hoppers were investigated at concentrations ranging from 0.16 to 1000 mg/L. At the concentration of 1000 mg/L and 500 mg/L, the lethal rate was 100%. Good insecticidal activity at 4 mg/L was still shown, especially against the black bean aphids and brown plant hoppers. Moreover, the photostability of the conjugate was evaluated and showed an apparent improvement. At 300 mins, the residual rate of the conjugate was 11.22%, much higher than 0.2% of the avermectin technical material. The conjugate we developed showed potential for further study and application in crop protection. Yan Li, Yukun Qin, Song Liu, Ronge Xing, Huahua Yu, Kecheng Li, and Pengcheng Li Copyright © 2016 Yan Li et al. All rights reserved. In Vitro Cytokine Expression and In Vivo Healing and Inflammatory Response to a Collagen-Coated Synthetic Bone Filler Mon, 18 Apr 2016 16:33:42 +0000 The goal of the present work was to investigate the relationship between in vivo healing and inflammatory response and in vitro cytokine expression by macrophages of a synthetic bone filler (25% hydroxylapatite-75% β-tricalcium phosphate) bearing a surface nanolayer of collagen. A clinically accepted, state-of-the-art xenograft material was used as a “negative control,” that is, as a material that provides the correct clinical response for the intended use. In vitro data show that both materials exert a very low stimulation of proinflammatory cytokines by macrophages, and this was confirmed by the very mild inflammatory response detected in in vivo tests of local response in a rabbit model. Also, in vitro findings suggest a different mechanism of healing for the test and the control material, with a higher regenerative activity for the synthetic, resorbable filler, as confirmed by in vivo observation and literature reports. Thus, the simple in vitro model adopted provides a reasonable forecast of in vivo results, suggesting that new product development can be guided by in vitro tuning of cell-materials interactions. Daniele Bollati, Marco Morra, Clara Cassinelli, Saturnino Marco Lupi, and Ruggero Rodriguez y Baena Copyright © 2016 Daniele Bollati et al. All rights reserved. LED Curing Lights and Temperature Changes in Different Tooth Sites Mon, 18 Apr 2016 14:16:48 +0000 Objectives. The aim of this in vitro study was to assess thermal changes on tooth tissues during light exposure using two different LED curing units. The hypothesis was that no temperature increase could be detected within the dental pulp during polymerization irrespective of the use of a composite resin or a light-curing unit. Methods. Caries-free human first molars were selected, pulp residues were removed after root resection, and four calibrated type-J thermocouples were positioned. Two LED lamps were tested; temperature measurements were made on intact teeth and on the same tooth during curing of composite restorations. The data was analyzed by one-way analysis of variance (ANOVA), Wilcoxon test, Kruskal-Wallis test, and Pearson’s . After ANOVA, the Bonferroni multiple comparison test was performed. Results. Polymerization data analysis showed that in the pulp chamber temperature increase was higher than that without resin. Starlight PRO, in the same condition of Valo lamp, showed a lower temperature increase in pre- and intrapolymerization. A control group (without composite resin) was evaluated. Significance. Temperature increase during resin curing is a function of the rate of polymerization, due to the exothermic polymerization reaction, the energy from the light unit, and time of exposure. E. Armellin, G. Bovesecchi, P. Coppa, G. Pasquantonio, and L. Cerroni Copyright © 2016 E. Armellin et al. All rights reserved. Synergistic Effect of Carbon Nanotubes and Graphene on Diopside Scaffolds Sun, 10 Apr 2016 12:55:20 +0000 A synergetic effect between carbon nanotubes (CNTs) and graphene on diopside (Di) scaffolds was demonstrated. 3D network architecture in the matrix was formed through the 1D CNTs inlaid among the 2D graphene platelets (GNPs). The mechanical properties of the CNTs/GNPs/Di scaffolds were significantly improved compared with the CNTs/Di scaffolds and GNPs/Di scaffolds. In addition, the scaffolds exhibited excellent apatite-forming ability, a modest degradation rate, and stable mechanical properties in simulated body fluid (SBF). Moreover, cell culturing tests indicated that the scaffolds supported the cells attachment and proliferation. Taken together, the CNTs/GNPs/Di scaffolds offered great potential for bone tissue engineering. Tingting Liu, Ping Wu, Chengde Gao, Pei Feng, Tao Xiao, Youwen Deng, Cijun Shuai, and Shuping Peng Copyright © 2016 Tingting Liu et al. All rights reserved. Utilizing Autologous Multipotent Mesenchymal Stromal Cells and -Tricalcium Phosphate Scaffold in Human Bone Defects: A Prospective, Controlled Feasibility Trial Thu, 07 Apr 2016 09:02:11 +0000 The purpose of this prospective controlled study was to compare healing quality following the implantation of ultraporous -tricalcium phosphate, containing either expanded autologous mesenchymal stromal cells (trial group, 9 patients) or -tricalcium phosphate alone (control group, 9 patients), into femoral defects during revision total hip arthroplasty. Both groups were assessed using the Harris Hip Score, radiography, and DEXA scanning at 6 weeks and 3, 6, and 12 months postoperatively. A significant difference in the bone defect healing was observed between both groups of patients (). In the trial group, trabecular remodeling was found in all nine patients and in the control group, in 1 patient only. Whereas, over the 12-month follow-up period, no significant difference was observed between both groups of patients in terms of the resorption of -tricalcium phosphate, the significant differences were documented in the presence of radiolucency and bone trabeculation through the defect (). Using autologous mesenchymal stromal cells combined with a -tricalcium phosphate scaffold is a feasible, safe, and effective approach for management of bone defects with compromised microenvironment. The clinical trial was registered at the EU Clinical Trials Register before patient recruitment has begun (EudraCT number 2012-005599-33). Pavel Šponer, Stanislav Filip, Tomáš Kučera, Jindra Brtková, Karel Urban, Vladimír Palička, Zuzana Kočí, Michael Syka, Aleš Bezrouk, and Eva Syková Copyright © 2016 Pavel Šponer et al. All rights reserved. Effect of the Crystallization Process on the Marginal and Internal Gaps of Lithium Disilicate CAD/CAM Crowns Thu, 31 Mar 2016 18:06:05 +0000 The aim of this study is to quantify the effect of the crystallization process on lithium disilicate ceramic crowns fabricated using a computer-aided design/computer-aided manufacturing (CAD/CAM) system and to determine whether the effect of crystallization is clinically acceptable by comparing values of fit before and after the crystallization process. The mandibular right first molar was selected as the abutment for the experiments. Fifteen working models were prepared. Lithium disilicate crowns appropriate for each abutment were prepared using a commercial CAD/CAM system. Gaps in the marginal area and 4 internal areas of each crown were measured twice—before and after crystallization—using the silicone replica technique. The mean values of fit before and after crystallization were analyzed using a paired -test to examine whether the conversion that occurred during crystallization affected marginal and internal gaps (). Gaps increased in the marginal area and decreased in the internal areas after crystallization. There were statistically significant differences in all of the investigated areas (). None of the values for marginal and internal fit of lithium disilicate CAD/CAM crowns after crystallization exceeded 120 μm, which is the clinically acceptable threshold. Jae-Hong Kim, Seunghan Oh, and Soo-Hyuk Uhm Copyright © 2016 Jae-Hong Kim et al. All rights reserved. Subtractive Cell-SELEX Selection of DNA Aptamers Binding Specifically and Selectively to Hepatocellular Carcinoma Cells with High Metastatic Potential Mon, 28 Mar 2016 16:29:28 +0000 Relapse and metastasis are two key risk factors of hepatocellular carcinoma (HCC) prognosis; thus, it is emergent to develop an early and accurate detection method for prognostic evaluation of HCC after surgery. In this study, we sought to acquire oligonucleotide DNA aptamers that specifically bind to HCC cells with high metastatic potential. Two HCC cell lines derived from the same genetic background but with different metastatic potential were employed: MHCC97L (low metastatic properties) as subtractive targets and HCCLM9 (high metastatic properties) as screening targets. To mimic a fluid combining environment, initial DNA aptamers library was firstly labelled with magnetic nanoparticles using biotin-streptavidin system and then applied for aptamers selection. Through 10-round selection with subtractive Cell-SELEX, six aptamers, LY-1, LY-13, LY-46, LY-32, LY-27/45, and LY-7/43, display high affinity to HCCLM9 cells and do not bind to MHCC97L cells, as well as other tumor cell lines, including breast cancer, lung cancer, colon adenocarcinoma, gastric cancer, and cervical cancer, suggesting high specificity for HCCLM9 cells. Thus, the aptamers generated here will provide solid basis for identifying new diagnostic targets to detect HCC metastasis and also may provide valuable clues for developing new targeted therapeutics. Hao Chen, Chun-Hui Yuan, Yi-Fei Yang, Chang-Qing Yin, Qing Guan, Fu-Bing Wang, and Jian-Cheng Tu Copyright © 2016 Hao Chen et al. All rights reserved. Facile Synthesis of Photofunctional Nanolayer Coatings on Titanium Substrates Thu, 24 Mar 2016 13:52:38 +0000 We developed a two-step chemical bonding process using photosensitizer molecules to fabricate photofunctional nanolayer coatings on hematoporphyrin- (HP-) coated Ti substrates. In the first step, 3-aminopropyltriethoxysilane was covalently functionalized onto the surface of the Ti substrates to provide heterogeneous sites for immobilizing the HP molecules. Then, HP molecules with carboxyl groups were chemically attached to the amine-terminated nanolayer coatings via a carbodiimide coupling reaction. The microstructure and elemental and phase composition of the HP-coated Ti substrates were investigated using field-emission scanning electron microscopy and energy-dispersive X-ray spectrometry. The photophysical properties of the photofunctional nanolayer coatings were confirmed using reflectance ultraviolet-visible absorption and emission spectrophotometry. The singlet oxygen generation efficiency of the photofunctional nanolayer coatings was determined using the decomposition reaction of 1,3-diphenylisobenzofuran. The HP-coated Ti substrates exhibited good biocompatibility without any cytotoxicity, and these nanolayer coatings generated singlet oxygen, which can kill microorganisms using only visible light. Kyong-Hoon Choi, Jung-Gil Kim, Byungman Kang, Ho-Joong Kim, and Bong Joo Park Copyright © 2016 Kyong-Hoon Choi et al. All rights reserved. Temperature Values Variability in Piezoelectric Implant Site Preparation: Differences between Cortical and Corticocancellous Bovine Bone Thu, 24 Mar 2016 08:09:11 +0000 Purpose. Various parameters can influence temperature rise and detection during implant site preparation. The aim of this study is to investigate local temperature values in cortical and corticocancellous bovine bone during early stages of piezoelectric implant site preparation. Materials and Methods. 20 osteotomies were performed using a diamond tip (IM1s, Mectron Medical Technology, Carasco, Italy) on two different types of bovine bone samples, cortical and corticocancellous, respectively. A standardized protocol was designed to provide constant working conditions. Temperatures were measured in real time at a fixed position by a fiber optic thermometer. Results. Significantly higher drilling time (154.90 sec versus 99.00 sec; ) and temperatures (39.26°C versus 34.73°C; ) were observed in the cortical group compared to the corticocancellous group. A remarkable variability of results characterized the corticocancellous blocks as compared to the blocks of pure cortical bone. Conclusion. Bone samples can influence heat generation during in vitro implant site preparation. When compared to cortical bone, corticocancellous samples present more variability in temperature values. Even controlling most experimental factors, the impact of bone samples still remains one of the main causes of temperature variability. Luca Lamazza, Girolamo Garreffa, Domenica Laurito, Marco Lollobrigida, Luigi Palmieri, and Alberto De Biase Copyright © 2016 Luca Lamazza et al. All rights reserved. Tissue Engineering and Dental Implantology: Biomaterials, New Technologies, and Stem Cells Thu, 17 Mar 2016 14:16:22 +0000 Gilberto Sammartino, David M. Dohan Ehrenfest, Jamil A. Shibli, and Pablo Galindo-Moreno Copyright © 2016 Gilberto Sammartino et al. All rights reserved. Effect of Extracellular Matrix Membrane on Bone Formation in a Rabbit Tibial Defect Model Mon, 07 Mar 2016 12:06:15 +0000 Absorbable extracellular matrix (ECM) membrane has recently been used as a barrier membrane (BM) in guided tissue regeneration (GTR) and guided bone regeneration (GBR). Absorbable BMs are mostly based on collagen, which is more biocompatible than synthetic materials. However, implanted absorbable BMs can be rapidly degraded by enzymes in vivo. In a previous study, to delay degradation time, collagen fibers were treated with cross-linking agents. These compounds prevented the enzymatic degradation of BMs. However, cross-linked BMs can exhibit delayed tissue integration. In addition, the remaining cross-linker could induce inflammation. Here, we attempted to overcome these problems using a natural ECM membrane. The membrane consisted of freshly harvested porcine pericardium that was stripped from cells and immunoreagents by a cleaning process. Acellular porcine pericardium (APP) showed a bilayer structure with a smooth upper surface and a significantly coarser bottom layer. APP is an ECM with a thin layer (0.18–0.35 mm) but with excellent mechanical properties. Tensile strength of APP was  MPa. In in vivo experiments, APP was transplanted into rabbit tibia. The biocompatible material was retained for up to 3 months without the need for cross-linking. Therefore, we conclude that APP could support osteogenesis as a BM for up to 3 months. Jin Wook Hwang, Sungtae Kim, Se Won Kim, and Jong Ho Lee Copyright © 2016 Jin Wook Hwang et al. All rights reserved. Analysis of Shear Bond Strength and Morphology of Er:YAG Laser-Recycled Ceramic Orthodontic Brackets Mon, 07 Mar 2016 06:48:50 +0000 Objective. The aim of this study was to compare the recycling of deboned ceramic brackets via an Er:YAG laser or via the traditional chairside processing methods of flaming and sandblasting; shear bond strength and morphological changes were evaluated in recycled brackets versus new brackets. Materials and Methods. 3M Clarity Self-Ligating Ceramic Brackets with a microcrystalline base were divided into groups subjected to flaming, sandblasting, or exposure to an Er:YAG laser. New ceramic brackets served as a control group. Shear bond strengths were determined with an Electroforce test machine and tested for statistical significance through analysis of variance. Morphological examinations of the recycled ceramic bracket bases were conducted with scanning electron microscopy and confocal laser scanning microscopy. Residue on the bracket base was analyzed with Raman spectroscopy. Results. Faded, dark adhesive was left on recycled bracket bases processed via flaming. Adhesive was thoroughly removed by both sandblasting and exposure to an Er:YAG laser. Compared with new brackets, shear bond strength was lower after sandblasting (), but not after exposure to an Er:YAG laser. The Er:YAG laser caused no damage to the bracket. Conclusion. Er:YAG lasers effectively remove adhesive from the bases of ceramic brackets without damaging them; thus, this method may be preferred over other recycling methods. Ruo-qiao Han, Kai Yang, Ling-fei Ji, and Chen Ling Copyright © 2016 Ruo-qiao Han et al. All rights reserved. Adsorption Analysis of Lactoferrin to Titanium, Stainless Steel, Zirconia, and Polymethyl Methacrylate Using the Quartz Crystal Microbalance Method Sun, 21 Feb 2016 16:46:58 +0000 It is postulated that biofilm formation in the oral cavity causes some oral diseases. Lactoferrin is an antibacterial protein in saliva and an important defense factor against biofilm development. We analyzed the adsorbed amount of lactoferrin and the dissociation constant (Kd) of lactoferrin to the surface of different dental materials using an equilibrium analysis technique in a 27 MHz quartz crystal microbalance (QCM) measurement. Four different materials, titanium (Ti), stainless steel (SUS), zirconia (ZrO2) and polymethyl methacrylate (PMMA), were evaluated. These materials were coated onto QCM sensors and the surfaces characterized by atomic force microscopic observation, measurements of surface roughness, contact angles of water, and zeta potential. QCM measurements revealed that Ti and SUS showed a greater amount of lactoferrin adsorption than ZrO2 and PMMA. Surface roughness and zeta potential influenced the lactoferrin adsorption. On the contrary, the Kd value analysis indicated that the adsorbed lactoferrin bound less tightly to the Ti and SUS surfaces than to the ZrO2 and PMMA surfaces. The hydrophobic interaction between lactoferrin and ZrO2 and PMMA is presumed to participate in better binding of lactoferrin to ZrO2 and PMMA surfaces. It was revealed that lactoferrin adsorption behavior was influenced by the characteristics of the material surface. Eiji Yoshida and Tohru Hayakawa Copyright © 2016 Eiji Yoshida and Tohru Hayakawa. All rights reserved. The Impact of Personality Traits on the Outcome of Total Knee Arthroplasty Thu, 18 Feb 2016 14:21:05 +0000 Ten to twenty percent of patients with total knee arthroplasty (TKA) are dissatisfied with their clinical outcome. Aim of this study was to investigate the impact of personality traits on the subjective outcome of TKA. We investigated 80 patients with 86 computer navigated TKAs. We asked for patients satisfaction and divided patients into two groups (satisfied or dissatisfied). 12 personality traits were tested by the Freiburg Personality Inventory (FPI-R). Postoperative examination included Knee Society Score (KSS), Western Ontario and McMaster University Osteoarthritis Index (WOMAC), and the Visual Analogue Scale (VAS). Radiologic investigation was done in all patients. 84% of our patients were satisfied, while 16% were not satisfied. The FPI-R showed statistical significant influence of four personality traits on patient satisfaction: life satisfaction (), performance orientation (), somatic distress (), and emotional stability (). All clinical scores (VAS, WOMAC, and KSS) showed significantly better results in the satisfied patient. Radiological examination showed optimal alignment of all TKAs. There were no complications requiring revision surgery. The results of our study show that personality traits may influence patients satisfaction and clinical outcome after TKA. Therefore patients personality traits may be a useful predictive factor for postoperative satisfaction after TKA. A. Giurea, G. Fraberger, P. Kolbitsch, R. Lass, E. Schneider, B. Kubista, and R. Windhager Copyright © 2016 A. Giurea et al. All rights reserved. Formation and Biopharmaceutical Characterization of Electrospun PVP Mats with Propolis and Silver Nanoparticles for Fast Releasing Wound Dressing Sun, 14 Feb 2016 11:25:04 +0000 Antibacterial, antiviral, antifungal, antioxidant, anti-inflammatory, and anticancer activities of propolis and its ability to stimulate the immune system and promote wound healing make it a proper component for wound dressing materials. Silver nanoparticles are recognized to demonstrate strong antiseptic and antimicrobial activity; thus, it also could be considered in the development of products for wound healing. Combining propolis and silver nanoparticles can result in improved characteristics of products designed for wound healing and care. The aim of this study was to formulate electrospun fast dissolving mats for wound dressing containing propolis ethanolic extract and silver nanoparticles. Produced electrospun nano/microfiber mats were evaluated studying their structure, dissolution rate, release of propolis phenolic compounds and silver nanoparticles, and antimicrobial activity. Biopharmaceutical characterization of electrospun mats demonstrated fast release of propolis phenolic compounds and silver nanoparticles. Evaluation of antimicrobial activity on Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris, Bacillus subtilis, Bacillus cereus, and Candida albicans strains confirmed the ability of electrospun mats to inhibit the growth of the tested microorganisms. Erika Adomavičiūtė, Sigitas Stanys, Modestas Žilius, Vaida Juškaitė, Alvydas Pavilonis, and Vitalis Briedis Copyright © 2016 Erika Adomavičiūtė et al. All rights reserved. Bioactive Materials for Bone Tissue Engineering Thu, 28 Jan 2016 17:28:32 +0000 Julietta V. Rau, Iulian Antoniac, Giuseppe Cama, Vladimir S. Komlev, and Antonio Ravaglioli Copyright © 2016 Julietta V. Rau et al. All rights reserved. Mechanical and Histological Effects of Resorbable Blasting Media Surface Treatment on the Initial Stability of Orthodontic Mini-Implants Thu, 28 Jan 2016 06:15:50 +0000 Introduction. This study aimed to evaluate the effects of resorbable blasting media (RBM) treatment on early stability of orthodontic mini-implants by mechanical, histomorphometric, and histological analyses. Methods. Ninety-six (64 for mechanical study and 32 for histological study and histomorphometric analysis) titanium orthodontic mini-implants (OMIs) with machined (machined group) or RBM-treated (CaP) surface (RBM group) were implanted in the tibiae of 24 rabbits. Maximum initial torque (MIT) was measured during insertion, and maximum removal torque (MRT) and removal angular momentum (RAM) were measured at 2 and 4 weeks after implantation. Bone-to-implant contact (BIC) and bone area (BA) were analyzed at 4 weeks after implantation. Results. RBM group exhibited significantly lower MIT and significantly higher MRT and RAM at 2 weeks than machined group. No significant difference in MRT, RAM, and BIC between the two groups was noted at 4 weeks, although BA was significantly higher in RBM group than in machined group. RBM group showed little bone resorption, whereas machined group showed new bone formation after bone resorption. Conclusions. RBM surface treatment can provide early stability of OMIs around 2 weeks after insertion, whereas stability of machined surface OMIs may decrease in early stages because of bone resorption, although it can subsequently recover by new bone apposition. Odontuya Gansukh, Jong-Wha Jeong, Jong-Wan Kim, Jong-Ho Lee, and Tae-Woo Kim Copyright © 2016 Odontuya Gansukh et al. All rights reserved. An In Vitro Comparison of PMMA and Calcium Sulfate as Carriers for the Local Delivery of Gallium(III) Nitrate to Staphylococcal Infected Surgical Sites Sun, 17 Jan 2016 12:16:41 +0000 Antibiotic-loaded bone cements, including poly(methyl methacrylate) (PMMA) and calcium sulfate (CaSO4), are often used for treatment of orthopaedic infections involving Staphylococcus spp., although the effectiveness of this treatment modality may be limited due to the emergence of antimicrobial resistance and/or the development of biofilms within surgical sites. Gallium(III) is an iron analog capable of inhibiting essential iron-dependent pathways, exerting broad antimicrobial activity against multiple microorganisms, including Staphylococcus spp. Herein, we evaluated PMMA and CaSO4 as carriers for delivery of gallium(III) nitrate (Ga(NO3)3) to infected surgical sites by assessing the release kinetics subsequent to incorporation and antimicrobial activity against S. aureus and S. epidermidis. PMMA and to a lesser extent CaSO4 were observed to be compatible as carriers for Ga(NO3)3, eluting concentrations with antimicrobial activity against planktonic bacteria, inhibiting bacterial growth, and preventing bacterial colonization of beads, and effective against established bacterial biofilms of S. aureus and S. epidermidis. Collectively, our in vitro results indicate that PMMA is a more suitable carrier compared to CaSO4 for delivery of Ga(NO3)3; moreover they provide evidence for the potential use of Ga(NO3)3 with PMMA as a strategy for the prevention and/or treatment for orthopaedic infections. Rebecca A. Garcia, David J. Tennent, David Chang, Joseph C. Wenke, and Carlos J. Sanchez Jr. Copyright © 2016 Rebecca A. Garcia et al. All rights reserved. New Ti-Alloys and Surface Modifications to Improve the Mechanical Properties and the Biological Response to Orthopedic and Dental Implants: A Review Thu, 14 Jan 2016 14:21:50 +0000 Titanium implants are widely used in the orthopedic and dentistry fields for many decades, for joint arthroplasties, spinal and maxillofacial reconstructions, and dental prostheses. However, despite the quite satisfactory survival rates failures still exist. New Ti-alloys and surface treatments have been developed, in an attempt to overcome those failures. This review provides information about new Ti-alloys that provide better mechanical properties to the implants, such as superelasticity, mechanical strength, and corrosion resistance. Furthermore, in vitro and in vivo studies, which investigate the biocompatibility and cytotoxicity of these new biomaterials, are introduced. In addition, data regarding the bioactivity of new surface treatments and surface topographies on Ti-implants is provided. The aim of this paper is to discuss the current trends, advantages, and disadvantages of new titanium-based biomaterials, fabricated to enhance the quality of life of many patients around the world. Yvoni Kirmanidou, Margarita Sidira, Maria-Eleni Drosou, Vincent Bennani, Athina Bakopoulou, Alexander Tsouknidas, Nikolaos Michailidis, and Konstantinos Michalakis Copyright © 2016 Yvoni Kirmanidou et al. All rights reserved. Intraoral Digital Impressions for Virtual Occlusal Records: Section Quantity and Dimensions Sun, 10 Jan 2016 10:33:57 +0000 The purpose of this study was to locate the 3D spatial position mandibular cast and determine its occlusal contacts in a novel way by using an intraoral scanner as part of the virtual occlusal record procedure. This study also analyzes the requirements in quantity and dimensions of the intraoral virtual occlusal record. The results showed that the best section combination consists of 2 lateral and frontal sections, the width of this section being that of 2 teeth (24 mm × 15 mm). This study concluded that this procedure was accurate enough to locate the mandibular cast on a virtual articulator. However, at least 2 sections of the virtual occlusal records were necessary, and the best results were obtained when the distance between these sections was maximum. Eneko Solaberrieta, Asier Garmendia, Aritza Brizuela, Jose Ramon Otegi, Guillermo Pradies, and Andras Szentpétery Copyright © 2016 Eneko Solaberrieta et al. All rights reserved. Findings of a Four-Year Randomized Controlled Clinical Trial Comparing Two-Piece and One-Piece Zirconia Abutments Supporting Single Prosthetic Restorations in Maxillary Anterior Region Mon, 04 Jan 2016 06:02:35 +0000 The purpose of this randomized controlled study is to investigate the clinical results obtained over four years and incidence of complications associated with one- versus two-piece custom made zirconia anchorages, in single tooth implant-supported restorations of the maxillary anterior region. Sixty-five patients, with a total of 74 missing maxillary teeth, were selected in the period from February 2007 to July 2010. Two different ways of custom made zirconia abutment and final prosthetic restoration were evaluated: a standard zirconia abutment associated with a pressed layer of lithium disilicate with an all-ceramic cemented restoration versus one-piece restoration with the facing porcelain fired and pressed straight to the custom made zirconia abutment. In 29 cases, the restoration consisted of an all-ceramic restoration for cementation (two pieces); in 45 cases the restoration was a screw-retained restoration (one piece). Three all-ceramic restorations broke during the observation time. Two one-piece restorations fractured after 26 months. At follow-up examination there were no significant differences between one-piece and two-piece groups regarding the PI, BI, and MBL. Awaiting studies with longer follow-up times, a careful conclusion is that zirconia anchorages for single-implant restorations seem to demonstrate good short-term technical and biological results. Guerino Paolantoni, Gaetano Marenzi, Andrea Blasi, Jolanda Mignogna, and Gilberto Sammartino Copyright © 2016 Guerino Paolantoni et al. All rights reserved. Analgesic Effect of Intra-Articular Injection of Temperature-Responsive Hydrogel Containing Bupivacaine on Osteoarthritic Pain in Rats Thu, 31 Dec 2015 10:46:25 +0000 The present study examined the analgesic effects of slow-releasing bupivacaine from hydrogel on chronic arthritic pain in rats. Osteoarthritis (OA) was induced by monosodium iodoacetate (MIA) injection into the right knee joint. Hydrogel (HG: 20, 30, and 50 μL) and temperature-sensitive hydrogel containing bupivacaine (T-gel: 20, 30, and 50 μL) were injected intra-articularly 14 days after MIA injection. Behavioral tests were conducted. The rats showed a significant decrease in weight load and paw withdrawal threshold (PWT). Intra-articular 0.5% bupivacaine (10 and 20 μL) significantly reversed MIA-induced decreased PWT, with no effect on weight load. In normal rats, hydrogel did not produce significant changes in PWT but at 30 and 50 μL slightly decreased weight bearing; T-gel did not cause any changes in both the weight load and PWT. In OA rats, T-gel at 20 μL had a significant analgesic effect for 2 days, even though T-gel at 50 μL further reduced the weight load, demonstrating that intra-articular T-gel (20 μL) has long-lasting analgesic effects in OA rats. Thus, T-gel designed to deliver analgesics into the joint cavity could be an effective therapeutic tool in the clinical setting. Taemin Kim, Dong Rim Seol, Suk-Chan Hahm, Cheolwoong Ko, Eun-Hye Kim, Keyoungjin Chun, Junesun Kim, and Tae-Hong Lim Copyright © 2015 Taemin Kim et al. All rights reserved. Effect of Air-Polishing on Titanium Surfaces, Biofilm Removal, and Biocompatibility: A Pilot Study Thu, 31 Dec 2015 06:06:19 +0000 Purpose. The aims of this in vitro study were to evaluate morphological changes induced by glycine powder air-polishing on titanium surfaces, biofilm removal, and biocompatibility. Material and Methods. Titanium grade IV discs were allocated into two groups: (1) discs without biofilm and (2) discs for Streptococcus mutans biofilm formation. Discs in each group were further subdivided into (a) no treatment and (b) air-polishing treatment with glycine powder. Discs were characterized by scanning electron microscopy (SEM), electron-dispersive spectroscopy (EDS), and confocal microscopy. Bacterial biofilms were quantified using a crystal violet dye-binding assay. Biocompatibility was evaluated by measuring the coverage and viability of L929 fibroblast cells cultured on the discs. Results. Air-polishing increased the roughness of treated discs (). EDS analysis did not show significant differences in the chemical composition of treated and nontreated discs. The amount of residual biofilm on treated discs was 8.6-fold lower than untreated controls (). Coverage of treated discs by fibroblasts was half that of untreated discs () although both groups had the same cell viability. Conclusions. Air-polishing removed a significant amount of biofilm from titanium surfaces. The “polishing” was accompanied by increased surface roughness, but there were no changes in chemical and elemental compositions, nor the biocompatibility. Vincent Bennani, Linda Hwang, Andrew Tawse-Smith, George J. Dias, and Richard D. Cannon Copyright © 2015 Vincent Bennani et al. All rights reserved. Metal-Free Restorations: Esthetic Considerations, Treatment Planning, Preparation, Manufacturing, Luting, and Followup Thu, 17 Dec 2015 14:04:03 +0000 Hamit S. Çötert, Handan Yılmaz, Cem Kurtoğlu, Flávio H. B. Aguiar, and Ahmet U. Güler Copyright © 2015 Hamit S. Çötert et al. All rights reserved. Tensile Bond Strengths of Two Adhesives on Irradiated and Nonirradiated Human Dentin Thu, 10 Dec 2015 12:47:35 +0000 The aim of this study was to assess the effect of radiotherapy on bond efficiency of two different adhesive systems using tensile bond strength test. Twenty extracted teeth after radiotherapy and twenty nonirradiated extracted teeth were used. The irradiation was applied in vivo to a minimal dose of 50 Gy. The specimens of each group were randomly assigned to two subgroups to test two different adhesive systems. A three-step/etch-and-rinse adhesive system (Optibond FL) and a two-steps/self-etch adhesive system (Optibond XTR) were used. Composite buildups were performed with a nanohybrid composite (Herculite XTR). All specimens were submitted to thermocycling ageing (10000 cycles). The specimens were sectioned in 1 mm2 sticks. Microtensile bond strength tests were measured. Nonparametric statistical analyses were performed due to nonnormality of data. Optibond XTR on irradiated and nonirradiated teeth did not show any significant differences. However, Optibond FL bond strength was more effective on nonirradiated teeth than on irradiated teeth. Within the limitations of an in vitro study, it can be concluded that radiotherapy had a significant detrimental effect on bond strength to human dentin. However, it seems that adhesive choice could be adapted to the substrata. According to the present study, the two-steps/self-etch (Optibond XTR) adhesive system tested could be more effective on irradiated dentin compared to three-steps/etch-and-rinse adhesive system (Optibond FL). Cécile Bernard, Cyril Villat, Hazem Abouelleil, Marie-Paule Gustin, and Brigitte Grosgogeat Copyright © 2015 Cécile Bernard et al. All rights reserved. Surgical Modification of the Murine Calvaria Osteolysis Model Thu, 03 Dec 2015 08:17:10 +0000 The murine calvaria model has been adopted for evaluation of osteolysis and inflammation induced by polyethylene (PE) or metal wear debris. However, this model suffers from several complications. The purpose of our study is to introduce a surgical modification with lower complication rates, thus providing more accurate results. Forty C57/BL6 mice were divided into two groups, both receiving polyethylene particles. Surgical modifications were performed in group 1, and group 2 underwent traditional surgeries. The incidence of fluid leakage was recorded on the operative day. Curst formation, wound dehiscence, and bone exposure were recorded on day 7. Histological osteolysis was demonstrated by HE staining of tissue slices. Micro-CT was used for quantifying evaluation of osteolysis in two groups. Intraoperative fluid leakage was significantly reduced in group 1. Postoperative crust formation, wound dehiscence, and bone exposure were also significantly decreased in group 1. HE staining results revealed obvious osteolysis in group 1 and more obvious osteolysis in group 2. Bone volume fraction (BVF) was (0.32 ± 0.03) in group 1 compared to group 2 (0.24 ± 0.05). Bone mineral density (BMD) was (1.11 ± 0.03) in group 1 compared to group 2 (1.01 ± 0.02). Surgical modifications provide a reliable way for establishment of the murine calvaria osteolysis model. Ali Mohammed Al-quhali, Yu Sun, Xizhuang Bai, Zhe Jin, and Guibo Yu Copyright © 2015 Ali Mohammed Al-quhali et al. All rights reserved. Ordinary and Activated Bone Grafts: Applied Classification and the Main Features Sun, 15 Nov 2015 12:13:28 +0000 Bone grafts are medical devices that are in high demand in clinical practice for substitution of bone defects and recovery of atrophic bone regions. Based on the analysis of the modern groups of bone grafts, the particularities of their composition, the mechanisms of their biological effects, and their therapeutic indications, applicable classification was proposed that separates the bone substitutes into “ordinary” and “activated.” The main differential criterion is the presence of biologically active components in the material that are standardized by qualitative and quantitative parameters: growth factors, cells, or gene constructions encoding growth factors. The pronounced osteoinductive and (or) osteogenic properties of activated osteoplastic materials allow drawing upon their efficacy in the substitution of large bone defects. R. V. Deev, A. Y. Drobyshev, I. Y. Bozo, and A. A. Isaev Copyright © 2015 R. V. Deev et al. All rights reserved. Increased Mesenchymal Stem Cell Response and Decreased Staphylococcus aureus Adhesion on Titania Nanotubes without Pharmaceuticals Tue, 10 Nov 2015 12:22:43 +0000 Titanium (Ti) implants with enhanced biocompatibility and antibacterial property are highly desirable and characterized by improved success rates. In this study, titania nanotubes (TNTs) with various tube diameters were fabricated on Ti surfaces through electrochemical anodization at 10, 30, and 60 V (denoted as NT10, NT30, and NT60, resp.). Ti was also investigated and used as a control. NT10 with a diameter of 30 nm could promote the adhesion and proliferation of bone marrow mesenchymal stem cells (BMSCs) without noticeable differentiation. NT30 with a diameter of 100 nm could support the adhesion and proliferation of BMSCs and induce osteogenesis. NT60 with a diameter of 200 nm demonstrated the best ability to promote cell spreading and osteogenic differentiation; however, it clearly impaired cell adhesion and proliferation. As the tube diameter increased, bacterial adhesion on the TNTs decreased and reached the lowest value on NT60. Therefore, NT30 without pharmaceuticals could be used to increase mesenchymal stem cell response and decrease Staphylococcus aureus adhesion and thus should be further studied for improving the efficacy of Ti-based orthopedic implants. Zhiqiang Xu, Yingzhen Lai, Dong Wu, Wenxiu Huang, Sijia Huang, Lin Zhou, and Jiang Chen Copyright © 2015 Zhiqiang Xu et al. All rights reserved. Long-Term In Vitro Degradation of a High-Strength Brushite Cement in Water, PBS, and Serum Solution Mon, 26 Oct 2015 07:43:29 +0000 Bone loss and fractures may call for the use of bone substituting materials, such as calcium phosphate cements (CPCs). CPCs can be degradable, and, to determine their limitations in terms of applications, their mechanical as well as chemical properties need to be evaluated over longer periods of time, under physiological conditions. However, there is lack of data on how the in vitro degradation affects high-strength brushite CPCs over longer periods of time, that is, longer than it takes for a bone fracture to heal. This study aimed at evaluating the long-term in vitro degradation properties of a high-strength brushite CPC in three different solutions: water, phosphate buffered saline, and a serum solution. Microcomputed tomography was used to evaluate the degradation nondestructively, complemented with gravimetric analysis. The compressive strength, chemical composition, and microstructure were also evaluated. Major changes from 10 weeks onwards were seen, in terms of formation of a porous outer layer of octacalcium phosphate on the specimens with a concomitant change in phase composition, increased porosity, decrease in object volume, and mechanical properties. This study illustrates the importance of long-term evaluation of similar cement compositions to be able to predict the material’s physical changes over a relevant time frame. Ingrid Ajaxon, Caroline Öhman, and Cecilia Persson Copyright © 2015 Ingrid Ajaxon et al. All rights reserved. Dental Implants Fatigue as a Possible Failure of Implantologic Treatment: The Importance of Randomness in Fatigue Behaviour Sun, 25 Oct 2015 12:35:39 +0000 Objective. To show how random variables concern fatigue behaviour by a probabilistic finite element method. Methods. Uncertainties on material properties due to the existence of defects that cause material elastic constant are not the same in the whole dental implant the dimensions of the structural element and load history have a decisive influence on the fatigue process and therefore on the life of a dental implant. In order to measure these uncertainties, we used a method based on Markoff chains, Bogdanoff and Kozin cumulative damage model, and probabilistic finite elements method. Results. The results have been obtained by conventional and probabilistic methods. Mathematical models obtained the same result regarding fatigue life; however, the probabilistic model obtained a greater mean life but with more information because of the cumulative probability function. Conclusions. The present paper introduces an improved procedure to study fatigue behaviour in order to know statistics of the fatigue life (mean and variance) and its probability of failure (fatigue life versus probability of failure). María Prados-Privado, Juan Carlos Prados-Frutos, Ángel Manchón, Rosa Rojo, Pietro Felice, and José Antonio Bea Copyright © 2015 María Prados-Privado et al. All rights reserved. Quantitative Evaluation of Tissue Surface Adaption of CAD-Designed and 3D Printed Wax Pattern of Maxillary Complete Denture Sun, 25 Oct 2015 09:48:58 +0000 Objective. To quantitatively evaluate the tissue surface adaption of a maxillary complete denture wax pattern produced by CAD and 3DP. Methods. A standard edentulous maxilla plaster cast model was used, for which a wax pattern of complete denture was designed using CAD software developed in our previous study and printed using a 3D wax printer, while another wax pattern was manufactured by the traditional manual method. The cast model and the two wax patterns were scanned in the 3D scanner as “DataModel,” “DataWaxRP,” and “DataWaxManual.” After setting each wax pattern on the plaster cast, the whole model was scanned for registration. After registration, the deviations of tissue surface between “DataModel” and “DataWaxRP” and between “DataModel” and “DataWaxManual” were measured. The data was analyzed by paired t-test. Results. For both wax patterns produced by the CAD&RP method and the manual method, scanning data of tissue surface and cast surface showed a good fit in the majority. No statistically significant () difference was observed between the CAD&RP method and the manual method. Conclusions. Wax pattern of maxillary complete denture produced by the CAD&3DP method is comparable with traditional manual method in the adaption to the edentulous cast model. Hu Chen, Han Wang, Peijun Lv, Yong Wang, and Yuchun Sun Copyright © 2015 Hu Chen et al. All rights reserved. Biological Behaviour and Enhanced Anticorrosive Performance of the Nitrided Superelastic Ti-23Nb-0.7Ta-2Zr-0.5N Alloy Sun, 25 Oct 2015 09:43:31 +0000 The influence of gas nitriding surface treatment on the superelastic Ti-23Nb-0.7Ta-2Zr-0.5N alloy was evaluated. A thorough characterization of bare and nitrided Ti-based alloy and pure Ti was performed in terms of surface film composition and morphology, electrochemical behaviour, and short term osteoblast response. XPS analysis showed that the nitriding treatment strongly influenced the composition (nitrides and oxynitrides) and surface properties both of the substrate and of the bulk alloy. SEM images revealed that the nitrided surface appears as a similar dotted pattern caused by the formation of N-rich domains coexisting with less nitrided domains, while before treatment only topographical features could be observed. All the electrochemical results confirmed the high chemical stability of the nitride and oxynitride coating and the superiority of the applied treatment. The values of the corrosion parameters ascertained the excellent corrosion resistance of the coated alloy in the real functional conditions from the human body. Cell culture experiments with MG63 osteoblasts demonstrated that the studied biomaterials do not elicit any toxic effects and support cell adhesion and enhanced cell proliferation. Altogether, these data indicate that the nitrided Ti-23Nb-0.7Ta-2Zr-0.5N alloy is the most suitable substrate for application in bone implantology. Valentina Mitran, Cora Vasilescu, Silviu Iulian Drob, Petre Osiceanu, Jose Maria Calderon-Moreno, Mariana-Cristina Tabirca, Doina-Margareta Gordin, Thierry Gloriant, and Anisoara Cimpean Copyright © 2015 Valentina Mitran et al. All rights reserved. An Overview of the Mechanical Integrity of Dental Implants Sun, 25 Oct 2015 09:22:36 +0000 With the growing use of dental implants, the incidence of implants’ failures grows. Late treatment complications, after reaching full osseointegration and functionality, include mechanical failures, such as fracture of the implant and its components. Those complications are deemed severe in dentistry, albeit being usually considered as rare, and therefore seldom addressed in the clinical literature. The introduction of dental implants into clinical practice fostered a wealth of research on their biological aspects. By contrast, mechanical strength and reliability issues were seldom investigated in the open literature, so that most of the information to date remains essentially with the manufacturers. Over the years, implants have gone through major changes regarding the material, the design, and the surface characteristics aimed at improving osseointegration. Did those changes improve the implants’ mechanical performance? This review article surveys the state-of-the-art literature about implants’ mechanical reliability, identifying the known causes for fracture, while outlining the current knowledge-gaps. Recent results on various aspects of the mechanical integrity and failure of implants are presented and discussed next. The paper ends by a general discussion and suggestions for future research, outlining the importance of mechanical considerations for the improvement of their future performance. Keren Shemtov-Yona and Daniel Rittel Copyright © 2015 Keren Shemtov-Yona and Daniel Rittel. All rights reserved. Hexosamine-Induced TGF-β Signaling and Osteogenic Differentiation of Dental Pulp Stem Cells Are Dependent on N-Acetylglucosaminyltransferase V Sun, 25 Oct 2015 07:20:53 +0000 Glycans of cell surface glycoproteins are involved in the regulation of cell migration, growth, and differentiation. N-acetyl-glucosaminyltransferase V (GnT-V) transfers N-acetyl-d-glucosamine to form β1,6-branched N-glycans, thus playing a crucial role in the biosynthesis of glycoproteins. This study reveals the distinct expression of GnT-V in STRO-1 and CD-146 double-positive dental pulp stem cells (DPSCs). Furthermore, we investigated three types of hexosamines and their N-acetyl derivatives for possible effects on the osteogenic differentiation potential of DPSCs. Our results showed that exogenous d-glucosamine (GlcN), N-acetyl-d-glucosamine (GlcNAc), d-mannosamine (ManN), and acetyl-d-mannosamine (ManNAc) promoted DPSCs’ early osteogenic differentiation in the absence of osteogenic supplements, but d-galactosamine (GalN) or N-acetyl-galactosamine (GalNAc) did not. Effects include the increased level of TGF-β receptor type I, activation of TGF-β signaling, and increased mRNA expression of osteogenic differentiation marker genes. The hexosamine-treated DPSCs showed an increased mineralized matrix deposition in the presence of osteogenic supplements. Moreover, the level of TGF-β receptor type I and early osteogenic differentiation were abolished in the DPSCs transfected with siRNA for GnT-V knockdown. These results suggest that GnT-V plays a critical role in the hexosamine-induced activation of TGF-β signaling and subsequent osteogenic differentiation of DPSCs. Yi-Jane Chen, Chung-Chen Yao, Chien-Hsun Huang, Hao-Hueng Chang, and Tai-Horng Young Copyright © 2015 Yi-Jane Chen et al. All rights reserved. Photocatalytical Antibacterial Activity of Mixed-Phase TiO2 Nanocomposite Thin Films against Aggregatibacter actinomycetemcomitans Wed, 21 Oct 2015 13:52:13 +0000 Mixed-phase nanocomposite thin films consisting of anatase and rutile prepared on commercially pure Ti sheets via the electrochemical anodization and annealing treatments were investigated in terms of their photocatalytic activity for antibacterial use around dental implants. The resulting films were characterized by scanning electron microscopy (SEM), and X-ray diffraction (XRD). The topology was assessed by White Light Optical Profiling (WLOP) in the Vertical Scanning Interferometer (VSI) mode. Representative height descriptive parameters of roughness and were calculated. The photocatalytic activity of the resulting films was evaluated by the photodegradation of Rhodamine B (RhB) dye solution. The antibacterial ability of the photocatalyst was examined by  Aggregatibacter actinomycetemcomitans suspensions in a colony-forming assay. XRD showed that anatase/rutile mixed-phase thin films were predominantly in anatase and rutile that were 54.6 wt% and 41.9 wt%, respectively. Craters (2–5 µm) and protruding hills (10–50 µm) on Ti substrates were produced after electrochemical anodization with higher and surface roughness values. Anatase/rutile mixed-phase thin films showed 26% photocatalytic decolorization toward RhB dye solution. The number of colonizing bacteria on anatase/rutile mixed-phase thin films was decreased significantly in vitro. The photocatalyst was effective against A. actinomycetemcomitans colonization. Sinem Yeniyol, Ilven Mutlu, Zhiming He, Behiye Yüksel, Robert Joseph Boylan, Mustafa Ürgen, Zihni Cüneyt Karabuda, Cansu Basegmez, and John Lawrence Ricci Copyright © 2015 Sinem Yeniyol et al. All rights reserved. Fracture Strength of Aged Monolithic and Bilayer Zirconia-Based Crowns Wed, 21 Oct 2015 11:57:00 +0000 The purpose of this study was to evaluate the effect of design and surface finishing on fracture strength of yttria-tetragonal zirconia polycrystal (Y-TZP) crowns in monolithic (1.5 mm thickness) and bilayer (0.8 mm zirconia coping and 0.7 mm porcelain veneer) configuration after artificial aging. Bovine incisors received crown preparation and Y-TZP crowns were manufactured using CAD/CAM technique, according to the following groups (): Polished monolithic zirconia crowns (PM); Glazed monolithic zirconia crowns (GM); Bi-layer crowns (BL). Crowns were cemented with resin cement, submitted to artificial aging in a chewing simulator (2.5 million cycles/80 N/artificial saliva/37°C), and tested for fracture strength. Two remaining crowns referring to PM and GM groups were submitted to a chemical composition analysis to measure the level of yttrium after aging. One-way ANOVA and Tukey’s test () indicated that monolithic zirconia crowns presented similar fracture strength ( N ± 791.7;  N ± 991.6), which was higher than bilayer crowns (2060.4 N ± 810.6). There was no difference in the yttrium content among the three surfaces evaluated in the monolithic crowns. Thus, monolithic zirconia crowns present higher fracture strength than bilayer veneered zirconia after artificial aging and surface finishing does not affect their fracture strength. Deborah Pacheco Lameira, Wilkens Aurélio Buarque e Silva, Frederico Andrade e Silva, and Grace M. De Souza Copyright © 2015 Deborah Pacheco Lameira et al. All rights reserved. Comparison of Conventional Methods and Laser-Assisted Rapid Prototyping for Manufacturing Fixed Dental Prostheses: An In Vitro Study Wed, 21 Oct 2015 09:00:09 +0000 This study assessed whether there are differences in marginal fit between laser-fusion and conventional techniques to produce fixed dental prostheses (FDPs). A master steel die with 2 abutments was produced to receive a posterior 4-unit FDPs and single copings. These experimental models were divided into three groups (/group) manufactured: group 1, Ni-Cr alloy, with a lost-wax casting technique; group 2, Co-Cr alloy, with selective laser melting (SLM); and group 3, yttria-tetragonal zirconia polycrystal (Y-TZP), with a milling system. All specimens were cut along the longitudinal axis and their adaptation was measured at the marginal and shoulder areas on the right and left sides of each abutment. Measurements were made using a stereomicroscope (×60 magnification) and a scanning electron microscope (×800 magnification). The data were analyzed using one-way analysis of variance and the Bonferroni post hoc test, with a significance cutoff of 5%. Significant differences () were observed between group 3 and the other groups. The marginal opening was smallest with Co-Cr alloy substructures, while the shoulder opening was smallest with Ni-Cr alloy substructures. Within the limitations of this study, the marginal fit of an FDP is better with rapid prototyping (RP) via SLM than conventional manufacturing systems. Giorgio Pompa, Stefano Di Carlo, Francesca De Angelis, Maria Paola Cristalli, and Susanna Annibali Copyright © 2015 Giorgio Pompa et al. All rights reserved. 3D Surface Profile and Color Stability of Tooth Colored Filling Materials after Bleaching Mon, 19 Oct 2015 09:40:31 +0000 This study aims to evaluate the effects of vital tooth bleaching with carbamide peroxide home bleaching and in-office bleaching on the color stability and 3D surface profile of dental restorative filling materials. Thirty discs () measure 6 mm in diameter and 2 mm thick for each of three restorative materials. These are nanofilled composite Filtek Z350 XT, the submicron composite Estelite Quick, and nanofilled glass ionomer Ketac N100 nanoionomer and were fabricated in shade A2. Each group was further divided into three subgroups (): subgroup A (Opalescence PF), subgroup B (Opalescence Boost in-office bleaching), and subgroup C (distilled water) serving as control. Samples were bleached according to the manufacturer’s instructions for a period of two weeks. The Commission Internationale de L’Eclairage (CIE , , ) system was chosen for image processing, while 3D surface profile was tested with atomic force microscopy (AFM). Statistical analyses were performed with the Mann-Whitney tests and Krusal-Wallis with a value of ≤0.05. The three restorative materials showed significant color changes (); . In diminishing order, the mean color changes recorded were Estelite (3.82 ± 1.6) > Ketac Nano (2.97 ± 1.2) > Filtek Z350 XT (2.25 ± 1.0). However, none of the tested materials showed statistically significant changes in surface roughness; . Bryant Anthony Irawan, Stacey Natalie Irawan, Sam’an Malik Masudi, Ninin Sukminingrum, and Mohammad Khursheed Alam Copyright © 2015 Bryant Anthony Irawan et al. All rights reserved. Cementation of Glass-Ceramic Posterior Restorations: A Systematic Review Sun, 18 Oct 2015 13:35:28 +0000 Aim. The aim of this comprehensive review is to systematically organize the current knowledge regarding the cementation of glass-ceramic materials and restorations, with an additional focus on the benefits of Immediate Dentin Sealing (IDS). Materials and Methods. An extensive literature search concerning the cementation of single-unit glass-ceramic posterior restorations was conducted in the databases of MEDLINE (Pubmed), CENTRAL (Cochrane Central Register of Controlled Trials), and EMBASE. To be considered for inclusion, in vitro and in vivo studies should compare different cementation regimes involving a “glass-ceramic/cement/human tooth” complex. Results and Conclusions. 88 studies were included in total. The in vitro data were organized according to the following topics: (micro)shear and (micro)tensile bond strength, fracture strength, and marginal gap and integrity. For in vivo studies survival and quality of survival were considered. In vitro studies showed that adhesive systems (3-step, etch-and-rinse) result in the best (micro)shear bond strength values compared to self-adhesive and self-etch systems when luting glass-ceramic substrates to human dentin. The highest fracture strength is obtained with adhesive cements in particular. No marked clinical preference for one specific procedure could be demonstrated on the basis of the reviewed literature. The possible merits of IDS are most convincingly illustrated by the favorable microtensile bond strengths. No clinical studies regarding IDS were found. Carline R. G. van den Breemer, Marco M. M. Gresnigt, and Marco S. Cune Copyright © 2015 Carline R. G. van den Breemer et al. All rights reserved. Real-Time Analysis of Temperature Changes in Composite Increments and Pulp Chamber during Photopolymerization Sun, 18 Oct 2015 12:28:51 +0000 Objective. The aim of this study was to evaluate the temperature change at various sites within the composite and on the pulpal side of dentin during polymerization of two composite increments. Materials and Methods. Class I cavities prepared in third molars were restored in two composite increments (). Temperatures were measured for 110 s using eight thermocouples: bottom center of cavity (BC), top center of 1st increment (MC), top center of 2nd increment (TC), bottom corner of cavity (BE), top corner of 1st increment (ME), top corner of 2nd increment (TE), pulpal side of dentin (PD), and center of curing light guide tip (CL). Results. Maximum temperature values (°C) measured during polymerization of 1st increment were MC (59.8); BC (52.8); ME (51.3); CL (50.7); BE (48.4); and PD (39.8). Maximum temperature values during polymerization of 2nd increment were TC 58.5; TE (52.6); MC (51.7); CL (50.0); ME (48.0); BC (46.7); BE (44.5); and PD (38.8). Conclusion. Temperature at the floor of the cavity was significantly higher during polymerization of 1st increment compared to 2nd increment. Temperature rise was higher at the center than at the corner and at the top surface than at the bottom surface of each increment. Ryan Jin-Young Kim, In-Bog Lee, Jin-Young Yoo, Su-Jung Park, Sin-Young Kim, Young-Ah Yi, Ji-Yun Hwang, and Deog-Gyu Seo Copyright © 2015 Ryan Jin-Young Kim et al. All rights reserved. Effects of Computer-Aided Manufacturing Technology on Precision of Clinical Metal-Free Restorations Sun, 18 Oct 2015 12:09:58 +0000 Purpose. The purpose of this study was to investigate the marginal fit of metal-free crowns made by three different computer-aided design/computer-aided manufacturing (CAD/CAM) systems. Materials and Methods. The maxillary left first premolar of a dentiform was prepared for all-ceramic crown restoration. Thirty all-ceramic premolar crowns were made, ten each manufactured by the Lava system, Cercon, and Cerec. Ten metal ceramic gold (MCG) crowns served as control. The marginal gap of each sample was measured under a stereoscopic microscope at 75x magnification after cementation. One-way ANOVA and the Duncan’s post hoc test were used for data analysis at the significance level of 0.05. Results. The mean (standard deviation) marginal gaps were 70.5 (34.4) μm for the MCG crowns, 87.2 (22.8) μm for Lava, 58.5 (17.6) μm for Cercon, and 72.3 (30.8) μm for Cerec. There were no significant differences in the marginal fit among the groups except that the Cercon crowns had significantly smaller marginal gaps than the Lava crowns .  Conclusions. Within the limitation of this study, all the metal-free restorations made by the digital CAD/CAM systems had clinically acceptable marginal accuracy. Ki-Hong Lee, In-Sung Yeo, Benjamin M. Wu, Jae-Ho Yang, Jung-Suk Han, Sung-Hun Kim, Yang-Jin Yi, and Taek-Ka Kwon Copyright © 2015 Ki-Hong Lee et al. All rights reserved. Analysis of Self-Adhesive Resin Cement Microshear Bond Strength on Leucite-Reinforced Glass-Ceramic with/without Pure Silane Primer or Universal Adhesive Surface Treatment Sun, 18 Oct 2015 12:06:16 +0000 Objective. To evaluate the microshear bond strength (μSBS) of self-adhesive resin (SA) cement on leucite-reinforced glass-ceramic using silane or universal adhesive. Materials and Methods. Ceramic blocks were etched with 9.5% hydrofluoric acid and divided into three groups (): (1) negative control (NC) without treatment; (2) Single Bond Universal (SBU); (3) RelyX Ceramic Primer as positive control (PC). RelyX Unicem resin cement was light-cured, and μSBS was evaluated with/without thermocycling. The μSBS was analyzed using one-way analysis of variance. The fractured surfaces were examined using stereomicroscopy and scanning electron microscopy (SEM). Results. Without thermocycling, μSBS was highest for PC (30.50 MPa ± 3.40), followed by SBU (27.33 MPa ± 2.81) and NC (20.18 MPa ± 2.01) (). Thermocycling significantly reduced μSBS in SBU (22.49 MPa ± 4.11) (), but not in NC (20.68 MPa ± 4.60) and PC (28.77 MPa ± 3.52) (). PC and NC predominantly fractured by cohesive failure within the ceramic and mixed failure, respectively. Conclusion. SBU treatment improves μSBS between SA cement and glass ceramics, but to a lower value than PC, and the improvement is eradicated by thermocycling. NC exhibited the lowest μSBS, which remained unchanged after thermocycling. Yoon Lee, Jae-Hoon Kim, Jung-Soo Woo, Young-Ah Yi, Ji-Yun Hwang, and Deog-Gyu Seo Copyright © 2015 Yoon Lee et al. All rights reserved. Bone Regeneration by Nanohydroxyapatite/Chitosan/Poly(lactide-co-glycolide) Scaffolds Seeded with Human Umbilical Cord Mesenchymal Stem Cells in the Calvarial Defects of the Nude Mice Tue, 13 Oct 2015 12:54:57 +0000 In the preliminary study, we have found an excellent osteogenic property of nanohydroxyapatite/chitosan/poly(lactide-co-glycolide) (nHA/CS/PLGA) scaffolds seeded with human umbilical cord mesenchymal stem cells (hUCMSCs) in vitro and subcutaneously in the nude mice. The aim of this study was to further evaluate the osteogenic capacity of nHA/CS/PLGA scaffolds seeded with hUCMSCs in the calvarial defects of the nude mice. Totally 108 nude mice were included and divided into 6 groups: PLGA scaffolds + hUCMSCs; nHA/PLGA scaffolds + hUCMSCs; CS/PLGA scaffolds + hUCMSCs; nHA/CS/PLGA scaffolds + hUCMSCs; nHA/CS/PLGA scaffolds without seeding; the control group (no scaffolds) (). The scaffolds were implanted into the calvarial defects of nude mice. The amount of new bones was evaluated by fluorescence labeling, H&E staining, and Van Gieson staining at 4 and 8 weeks, respectively. The results demonstrated that the amount of new bones was significantly increased in the group of nHA/CS/PLGA scaffolds seeded with hUCMSCs (). On the basis of previous studies in vitro and in subcutaneous implantation of the nude mice, the results revealed that the nHA and CS also enhanced the bone regeneration by nHA/CS/PLGA scaffolds seeded with hUCMSCs in the calvarial defects of the nude mice at early stage. Fei Wang, Xiao-Xia Su, Yu-Cheng Guo, Ang Li, Yin-Cheng Zhang, Hong Zhou, Hu Qiao, Li-Min Guan, Min Zou, and Xin-Qin Si Copyright © 2015 Fei Wang et al. All rights reserved. Shear Bond Strength of MDP-Containing Self-Adhesive Resin Cement and Y-TZP Ceramics: Effect of Phosphate Monomer-Containing Primers Sun, 11 Oct 2015 13:47:45 +0000 Purpose. This study was conducted to evaluate the effects of different phosphate monomer-containing primers on the shear bond strength between yttria-tetragonal zirconia polycrystal (Y-TZP) ceramics and MDP-containing self-adhesive resin cement. Materials and Methods. Y-TZP ceramic surfaces were ground flat with #600-grit SiC paper and divided into six groups (). They were treated as follows: untreated (control), Metal/Zirconia Primer, Z-PRIME Plus, air abrasion, Metal/Zirconia Primer with air abrasion, and Z-PRIME Plus with air abrasion. MDP-containing self-adhesive resin cement was applied to the surface-treated Y-TZP specimens. After thermocycling, a shear bond strength test was performed. The surfaces of the Y-TZP specimens were analyzed under a scanning electron microscope. The bond strength values were statistically analyzed using one-way analysis of variance and the Student–Newman–Keuls multiple comparison test (). Results. The Z-PRIME Plus treatment combined with air abrasion produced the highest bond strength, followed by Z-PRIME Plus application, Metal/Zirconia Primer combined with air abrasion, air abrasion alone, and, lastly, Metal/Zirconia Primer application. The control group yielded the lowest results (). Conclusion. The application of MDP-containing primer resulted in increased bond strength between Y-TZP ceramics and MDP-containing self-adhesive resin cements. Jin-Soo Ahn, Young-Ah Yi, Yoon Lee, and Deog-Gyu Seo Copyright © 2015 Jin-Soo Ahn et al. All rights reserved. Direct Tensile Strength and Characteristics of Dentin Restored with All-Ceramic, Resin-Composite, and Cast Metal Prostheses Cemented with Resin Adhesives Sun, 11 Oct 2015 13:36:47 +0000 A dentin-cement-prosthesis complex restored with either all-porcelain, cured resin-composite, or cast base metal alloy and cemented with either of the different resin cements was trimmed into a mini-dumbbell shape for tensile testing. The fractured surfaces and characterization of the dentin-cement interface of bonded specimens were investigated using a Scanning Electron Microscope. A significantly higher tensile strength of all-porcelain (12.5 ± 2.2 MPa) than that of cast metal (9.2 ± 3.5 MPa) restorations was revealed with cohesive failure in the cement and failure at the prosthesis-cement interface in Super-Bond C&B group. No significant difference in tensile strength was found among the types of restorations using the other three cements with adhesive failure on the dentin side and cohesive failure in the cured resin. SEM micrographs demonstrated the consistent hybridized dentin in Super-Bond C&B specimens that could resist degradation when immersed in hydrochloric acid followed by NaOCl solutions whereas a detached and degraded interfacial layer was found for the other cements. The results suggest that when complete hybridization of resin into dentin occurs tensile strength at the dentin-cement is higher than at the cement-prosthesis interfaces. The impermeable hybridized dentin can protect the underlying dentin and pulp from acid demineralization, even if detachment of the prosthesis has occurred. Morakot Piemjai and Nobuo Nakabayashi Copyright © 2015 Morakot Piemjai and Nobuo Nakabayashi. All rights reserved. In Vitro Behavior of Human Adipose Tissue-Derived Stem Cells on Poly(ε-caprolactone) Film for Bone Tissue Engineering Applications Thu, 08 Oct 2015 13:54:43 +0000 Bone tissue engineering is an emerging field, representing one of the most exciting challenges for scientists and clinicians. The possibility of combining mesenchymal stem cells and scaffolds to create engineered tissues has brought attention to a large variety of biomaterials in combination with osteoprogenitor cells able to promote and regenerate bone tissue. Human adipose tissue is officially recognized as an easily accessible source of mesenchymal stem cells (AMSCs), a significant factor for use in tissue regenerative medicine. In this study, we analyze the behavior of a clonal finite cell line derived from human adipose tissue seeded on poly(ε-caprolactone) (PCL) film, prepared by solvent casting. PCL polymer is chosen for its good biocompatibility, biodegradability, and mechanical properties. We observe that AMSCs are able to adhere to the biomaterial and remain viable for the entire experimental period. Moreover, we show that the proliferation process and osteogenic activity of AMSCs are maintained on the biofilm, demonstrating that the selected biomaterial ensures cell colonization and the development of an extracellular mineralized matrix. The results of this study highlight that AMSCs and PCL film can be used as a suitable model to support regeneration of new bone for future tissue engineering strategies. Cecilia Romagnoli, Roberto Zonefrati, Gianna Galli, Dario Puppi, Alessandro Pirosa, Federica Chiellini, Francesco Saverio Martelli, Annalisa Tanini, and Maria Luisa Brandi Copyright © 2015 Cecilia Romagnoli et al. All rights reserved. New Biomaterials in Drug Delivery and Wound Care Wed, 07 Oct 2015 07:26:21 +0000 Šeila Selimović, Francesco Piraino, Robert Gauvin, and Hojae Bae Copyright © 2015 Šeila Selimović et al. All rights reserved. Macrophage-Targeting Gene Delivery Using a Micelle Composed of Mannose-Modified Lipid with Triazole Ring and Dioleoyl Trimethylammonium Propane Mon, 05 Oct 2015 09:35:15 +0000 Gene carriers with cell specific ligand molecules are needed for the treatment of several diseases. Mannose is known to be recognized and incorporated into the cells through mannose recognition lectins that are exclusively expressed on macrophages. In this study, we synthesized two types of mannose-modified lipids with different stereoisomer (α-mannose and β-mannose). To make a complex with plasmid DNA (pDNA), termed “lipoplex,” we prepared a two-component micelle made from cationic lipid; dioleoyltrimethylammoniumpropane (DOTAP); and mannose-modified lipid (D/α-Man or D/β-Man). The prepared D/α-Man lipoplexes were able to bind to one of the α-mannose lectins concanavalin A (ConA) immobilized on gold substrate in the quartz-crystal microbalance sensor cell. D/β-Man lipoplexes did not show any frequency changes. These results indicate that the mannose residues were exposed on the lipoplexes, leading to not only the binding to ConA but also the prevention of nonspecific interactions with proteins. Both lipoplexes showed high transfection efficiencies to RAW264.7 cells which have several kinds of mannose lectins. This delivery system to macrophages may overcome the problems for gene therapy and may be used for the treatment of immune diseases involved in macrophages. Ichiki Fukuda, Shinichi Mochizuki, and Kazuo Sakurai Copyright © 2015 Ichiki Fukuda et al. All rights reserved. A Current View of Functional Biomaterials for Wound Care, Molecular and Cellular Therapies Mon, 05 Oct 2015 08:38:15 +0000 The intricate process of wound healing involves activation of biological pathways that work in concert to regenerate a tissue microenvironment consisting of cells and external cellular matrix (ECM) with enzymes, cytokines, and growth factors. Distinct stages characterize the mammalian response to tissue injury: hemostasis, inflammation, new tissue formation, and tissue remodeling. Hemostasis and inflammation start right after the injury, while the formation of new tissue, along with migration and proliferation of cells within the wound site, occurs during the first week to ten days after the injury. In this review paper, we discuss approaches in tissue engineering and regenerative medicine to address each of these processes through the application of biomaterials, either as support to the native microenvironment or as delivery vehicles for functional hemostatic, antibacterial, or anti-inflammatory agents. Molecular therapies are also discussed with particular attention to drug delivery methods and gene therapies. Finally, cellular treatments are reviewed, and an outlook on the future of drug delivery and wound care biomaterials is provided. Francesco Piraino and Šeila Selimović Copyright © 2015 Francesco Piraino and Šeila Selimović. All rights reserved. Biologic Agents for Periodontal Regeneration and Implant Site Development Mon, 05 Oct 2015 08:27:39 +0000 The advancement of molecular mediators or biologic agents has increased tremendously during the last decade in periodontology and dental implantology. Implant site development and reconstruction of the lost periodontium represent main fields in which these molecular mediators have been employed and investigated. Different growth factors trigger different reactions in the tissues of the periodontium at various cellular levels. Proliferation, migration, and differentiation constitute the main target areas of these molecular mediators. It was the purpose of this comprehensive review to describe the origin and rationale, evidence, and the most current understanding of the following biologic agents: Recombinant Human Platelet-Derived Growth Factor-BB (rhPDGF-BB), Enamel Matrix Derivate (EMD), Platelet-Rich Plasma (PRP) and Platelet-Rich Fibrin (PRF), Recombinant Human Fibroblast Growth Factor-2 (rhFGF-2), Bone Morphogenic Proteins (BMPs, BMP-2 and BMP-7), Teriparatide PTH, and Growth Differential Factor-5 (GDF-5). Fernando Suárez-López del Amo, Alberto Monje, Miguel Padial-Molina, ZhiHui Tang, and Hom-Lay Wang Copyright © 2015 Fernando Suárez-López del Amo et al. All rights reserved. Bone Regeneration from PLGA Micro-Nanoparticles Mon, 05 Oct 2015 08:23:55 +0000 Poly-lactic-co-glycolic acid (PLGA) is one of the most widely used synthetic polymers for development of delivery systems for drugs and therapeutic biomolecules and as component of tissue engineering applications. Its properties and versatility allow it to be a reference polymer in manufacturing of nano- and microparticles to encapsulate and deliver a wide variety of hydrophobic and hydrophilic molecules. It additionally facilitates and extends its use to encapsulate biomolecules such as proteins or nucleic acids that can be released in a controlled way. This review focuses on the use of nano/microparticles of PLGA as a delivery system of one of the most commonly used growth factors in bone tissue engineering, the bone morphogenetic protein 2 (BMP2). Thus, all the needed requirements to reach a controlled delivery of BMP2 using PLGA particles as a main component have been examined. The problems and solutions for the adequate development of this system with a great potential in cell differentiation and proliferation processes under a bone regenerative point of view are discussed. Inmaculada Ortega-Oller, Miguel Padial-Molina, Pablo Galindo-Moreno, Francisco O’Valle, Ana Belén Jódar-Reyes, and Jose Manuel Peula-García Copyright © 2015 Inmaculada Ortega-Oller et al. All rights reserved. Effects of P-15 Peptide Coated Hydroxyapatite on Tibial Defect Repair In Vivo in Normal and Osteoporotic Rats Mon, 05 Oct 2015 08:02:03 +0000 This study assessed the efficacy of anorganic bone mineral coated with P-15 peptide (ABM/P-15) on tibia defect repair longitudinally in both normal and osteoporotic rats in vivo. A paired design was used. 24 Norwegian brown rats were divided into normal and osteoporotic groups. 48 cylindrical defects were created in proximal tibias bilaterally. Defects were filled with ABM/P-15 or left empty. Osteoporotic status was assessed by microarchitectural analysis. Microarchitectural properties of proximal tibial defects were evaluated at 4 time points. 21 days after surgery, tibias were harvested for histology and histomorphometry. Significantly increased bone volume fraction, surface density, and connectivity were seen in all groups at days 14 and 21 compared with day 0. Moreover, the structure type of ABM/P-15 group was changed toward typical plate-like structure. Microarchitectural properties of ABM/P-15 treated newly formed bones at 21 days were similar in normal and osteoporotic rats. Histologically, significant bone formation was seen in all groups. Interestingly, significantly increased bone formation was seen in osteoporotic rats treated with ABM/P-15 indicating optimized healing potential. Empty defects showed lower healing potential in osteoporotic bone. In conclusion, ABM/P-15 accelerated bone regeneration in osteoporotic rats but did not enhance bone regeneration in normal rats. Rasmus Hestehave Pedersen, Marina Rasmussen, Søren Overgaard, and Ming Ding Copyright © 2015 Rasmus Hestehave Pedersen et al. All rights reserved. Naturally Occurring Extracellular Matrix Scaffolds for Dermal Regeneration: Do They Really Need Cells? Mon, 05 Oct 2015 07:55:49 +0000 The pronounced effect of extracellular matrix (ECM) scaffolds in supporting tissue regeneration is related mainly to their maintained 3D structure and their bioactive components. These decellularized matrix scaffolds could be revitalized before grafting via adding stem cells, fibroblasts, or keratinocytes to promote wound healing. We reviewed the online published literature in the last five years for the studies that performed ECM revitalization and discussed the results of these studies and the related literature. Eighteen articles met the search criteria. Twelve studies included adding cells to acellular dermal matrix (ADM), 3 studies were on small intestinal mucosa (SIS), one study was on urinary bladder matrix (UBM), one study was on amniotic membrane, and one study included both SIS and ADM loaded constructs. We believe that, in chronic and difficult-to-heal wounds, revitalizing the ECM scaffolds would be beneficial to overcome the defective host tissue interaction. This belief still has to be verified by high quality randomised clinical trials, which are still lacking in literature. A. M. Eweida and M. K. Marei Copyright © 2015 A. M. Eweida and M. K. Marei. All rights reserved. Custom-Made Antibiotic Cement Nails in Orthopaedic Trauma: Review of Outcomes, New Approaches, and Perspectives Mon, 05 Oct 2015 07:12:44 +0000 Since the first description in 2002 by Paley and Herzenberg, antibiotic bone cement nails (ACNs) have become an effective tool in the orthopaedic trauma surgeons’ hands. They simultaneously elute high amounts of antibiotics into medullary canal dead space and provide limited stability to the debrided long bone. In this paper, we perform a systematic review of current evidence on ACNs in orthopaedic trauma and provide an up-to-date review of the indications, operative technique, failure mechanisms, complications, outcomes, and outlooks for the ACNs use in long bone infection. Marcin K. Wasko and Rafal Kaminski Copyright © 2015 Marcin K. Wasko and Rafal Kaminski. All rights reserved. Twelve-Month Results of a Single or Multiple Dexamethasone Intravitreal Implant for Macular Edema following Uncomplicated Phacoemulsification Mon, 05 Oct 2015 07:10:16 +0000 The clinical efficacy of one or two intravitreal injections of a continued deliverance dexamethasone 700 μg implant in ten patients with persistent macular edema following uncomplicated phacoemulsification was evaluated. Complete ophthalmological examination and spectral domain optical coherence tomography were carried out. Follow-up was at day 7 and months 1, 2, 4, 6, 8, and 12. At baseline mean best corrected visual acuity was 62 Early Treatment Diabetic Retinopathy Study Chart letters, which showed statistically significant improvement at each follow-up, except at month 6, to reach 79 letters at month 12 (). Prior to treatment mean central foveal thickness was 622 μm, which showed statistically significant improvement at each follow-up to reach a mean value of 282 μm () at month 12. Five patients received a second dexamethasone implant at month 7. Two patients were excluded from the study at months 4 and 8. Intraocular pressure remained stable during the study period with the exception of mild increase in two patients requiring topical therapy. In conclusion there was statistically significant improvement of best corrected visual acuity and mean central foveal thickness with one or two intravitreal dexamethasone implants over 12 months. Solmaz Abdolrahimzadeh, Vito Fenicia, Maurizio Maurizi Enrici, Pasquale Plateroti, Dora Cianfrone, and Santi Maria Recupero Copyright © 2015 Solmaz Abdolrahimzadeh et al. All rights reserved. Microstereolithography-Based Fabrication of Anatomically Shaped Beta-Tricalcium Phosphate Scaffolds for Bone Tissue Engineering Sun, 04 Oct 2015 14:00:49 +0000 Porous ceramic scaffolds with shapes matching the bone defects may result in more efficient grafting and healing than the ones with simple geometries. Using computer-assisted microstereolithography (MSTL), we have developed a novel gelcasting indirect MSTL technology and successfully fabricated two scaffolds according to CT images of rabbit femur. Negative resin molds with outer 3D dimensions conforming to the femur and an internal structure consisting of stacked meshes with uniform interconnecting struts, 0.5 mm in diameter, were fabricated by MSTL. The second mold type was designed for cortical bone formation. A ceramic slurry of beta-tricalcium phosphate (-TCP) with room temperature vulcanization (RTV) silicone as binder was cast into the molds. After the RTV silicone was completely cured, the composite was sintered at 1500°C for 5 h. Both gross anatomical shape and the interpenetrating internal network were preserved after sintering. Even cortical structure could be introduced into the customized scaffolds, which resulted in enhanced strength. Biocompatibility was confirmed by vital staining of rabbit bone marrow mesenchymal stromal cells cultured on the customized scaffolds for 5 days. This fabrication method could be useful for constructing bone substitutes specifically designed according to local anatomical defects. Dajiang Du, Teruo Asaoka, Makoto Shinohara, Tomonori Kageyama, Takashi Ushida, and Katsuko Sakai Furukawa Copyright © 2015 Dajiang Du et al. All rights reserved. Collagen/Beta-Tricalcium Phosphate Based Synthetic Bone Grafts via Dehydrothermal Processing Sun, 04 Oct 2015 13:24:51 +0000 Millions of patients worldwide remain inadequately treated for bone defects related to factors such as disease or trauma. The drawbacks of metallic implant and autograft/allograft use have steered therapeutic approaches towards tissue engineering solutions involving tissue regeneration scaffolds. This study proposes a composite scaffold with properties tailored to address the macro- and microenvironmental conditions deemed necessary for successful regeneration of bone in defect areas. The biodegradable scaffold composed of porous beta-tricalcium phosphate particles and collagen type I fibers is prepared from a mixture of collagen type-I and β-tricalcium phosphate (β-TCP) particles via lyophilization, followed by dehydrothermal (DHT) processing. The effects of both sterilization via gamma radiation and the use of DHT processing to achieve cross-linking were investigated. The impact of the chosen fabrication methods on scaffold microstructure and β-TCP particle-collagen fiber combinations were analyzed using X-ray diffractometry (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and microcomputerized tomography (µ-CT). Electron spinning resonance (ESR) analysis was used to investigate free radicals formation following sterilization. Results revealed that the highly porous (65% porosity at an average of 100 µm pore size), mechanically adequate, and biocompatible scaffolds can be utilized for bone defect repairs. Burcu Sarikaya and Halil Murat Aydin Copyright © 2015 Burcu Sarikaya and Halil Murat Aydin. All rights reserved. Cutaneous and Labyrinthine Tolerance of Bioactive Glass S53P4 in Mastoid and Epitympanic Obliteration Surgery: Prospective Clinical Study Sun, 04 Oct 2015 13:19:35 +0000 Objective. To evaluate the cutaneous and the inner ear tolerance of bioactive glass S53P4 when used in the mastoid and epitympanic obliteration for chronic otitis surgery. Material and Methods. Forty-one cases have been included in this prospective study. Cutaneous tolerance was clinically evaluated 1 week, 1 month, and 3 months after surgery with a physical examination of the retroauricular and external auditory canal (EAC) skin and the presence of otalgia; the inner ear tolerance was assessed by bone-conduction hearing threshold 1 day after surgery and by the presence of vertigo or imbalance. Results. All surgeries but 1 were uneventful: all patients maintained the preoperative bone-conduction hearing threshold except for one case in which the round window membrane was opened during the dissection of the cholesteatoma in the hypotympanum and this led to a dead ear. No dizziness or vertigo was reported. Three months after surgery, healing was achieved in all cases with a healthy painless skin. No cases of revision surgery for removal of the granules occurred in this study. Conclusion. The bioactive glass S53P4 is a well-tolerated biomaterial for primary or revision chronic otitis surgery, as shown by the local skin reaction which lasted less than 3 months and by the absence of labyrinthine complications. Daniele Bernardeschi, Yann Nguyen, Francesca Yoshie Russo, Isabelle Mosnier, Evelyne Ferrary, and Olivier Sterkers Copyright © 2015 Daniele Bernardeschi et al. All rights reserved. In Vivo Osseointegration Performance of Titanium Dioxide Coating Modified Polyetheretherketone Using Arc Ion Plating for Spinal Implant Application Sun, 04 Oct 2015 12:52:03 +0000 Polyetheretherketone (PEEK), which has biomechanical performance similar to that of human cancellous bone, is used widely as a spinal implant material. However, its bioinertness and hydrophobic surface properties result in poor osseointegration. This study applies a novel modification method, arc ion plating (AIP), that produces a highly osteoblast compatible titanium dioxide (TiO2) coatings on a PEEK substrate. This PEEK with TiO2 coating (TiO2/PEEK) was implanted into the femurs of New Zealand white male rabbits to evaluate its in vivo performance by the push-out test and histological observation. Analytical results show that AIP can prepare TiO2 coatings on bullet-shaped PEEK substrates as implant materials. After prolonged implantation in rabbits, no signs of inflammation existed. Newly regenerated bone formed more prominently with the TiO2/PEEK implant by histological observation. The shear strength of the bone/implant interface increases as implantation period increases. Most importantly, bone bonding performance of the TiO2/PEEK implant was superior to that of bare PEEK. The rutile-TiO2 coatings achieved better osseointegration than the anatase-TiO2 coatings. Therefore, AIP-TiO2 can serve as a novel surface modification method on PEEK for spinal interbody fusion cages. Hsi-Kai Tsou, Meng-Hui Chi, Yi-Wen Hung, Chi-Jen Chung, and Ju-Liang He Copyright © 2015 Hsi-Kai Tsou et al. All rights reserved. Chitosan and Its Potential Use as a Scaffold for Tissue Engineering in Regenerative Medicine Sun, 04 Oct 2015 11:42:32 +0000 Tissue engineering is an important therapeutic strategy to be used in regenerative medicine in the present and in the future. Functional biomaterials research is focused on the development and improvement of scaffolding, which can be used to repair or regenerate an organ or tissue. Scaffolds are one of the crucial factors for tissue engineering. Scaffolds consisting of natural polymers have recently been developed more quickly and have gained more popularity. These include chitosan, a copolymer derived from the alkaline deacetylation of chitin. Expectations for use of these scaffolds are increasing as the knowledge regarding their chemical and biological properties expands, and new biomedical applications are investigated. Due to their different biological properties such as being biocompatible, biodegradable, and bioactive, they have given the pattern for use in tissue engineering for repair and/or regeneration of different tissues including skin, bone, cartilage, nerves, liver, and muscle. In this review, we focus on the intrinsic properties offered by chitosan and its use in tissue engineering, considering it as a promising alternative for regenerative medicine as a bioactive polymer. Martin Rodríguez-Vázquez, Brenda Vega-Ruiz, Rodrigo Ramos-Zúñiga, Daniel Alexander Saldaña-Koppel, and Luis Fernando Quiñones-Olvera Copyright © 2015 Martin Rodríguez-Vázquez et al. All rights reserved. A Comparison of the Process of Remodeling of Hydroxyapatite/Poly-D/L-Lactide and Beta-Tricalcium Phosphate in a Loading Site Sun, 04 Oct 2015 11:40:06 +0000 Currently, the most commonly used bioresorbable scaffold is made of beta-tricalcium phosphate (β-TCP); it is hoped that scaffolds made of a mixture of hydroxyapatite (HA) and poly-D/L-lactide (PDLLA) will be able to act as novel bioresorbable scaffolds. The aim of this study was to evaluate the utility of a HA/PDLLA scaffold compared to β-TCP, at a loading site. Dogs underwent surgery to replace a section of tibial bone with a bioresorbable scaffold. After the follow-up period, the scaffold was subjected to histological analysis. The HA/PDLLA scaffold showed similar bone formation and superior cell and tissue infiltration compared to the β-TCP scaffold, as seen after Villanueva Goldner staining. Moreover, silver staining and immunohistochemistry for Von Willebrand factor and cathepsin K demonstrated better cell infiltration in the HA/PDLLA scaffold. The fibrous tissue and cells that had infiltrated into the HA/PDLLA scaffold tested positive for collagen type I and RUNX2, respectively, indicating that the tissue and cells that had infiltrated into the HA/PDLLA scaffold had the potential to differentiate into bone. The HA/PDLLA scaffold is therefore likely to find clinical application as a new bioresorbable scaffold. Hiroyuki Akagi, Hiroki Ochi, Satoshi Soeta, Nobuo Kanno, Megumi Yoshihara, Kenshi Okazaki, Takuya Yogo, Yasuji Harada, Hajime Amasaki, and Yasushi Hara Copyright © 2015 Hiroyuki Akagi et al. All rights reserved. Histological Comparison in Rats between Carbonate Apatite Fabricated from Gypsum and Sintered Hydroxyapatite on Bone Remodeling Sun, 04 Oct 2015 11:29:53 +0000 Carbonate apatite (CO3Ap), the form of apatite found in bone, has recently attracted attention. The purpose of the present study was to histologically evaluate the tissue/cellular response toward the low-crystalline CO3Ap fabricated using a dissolution-precipitation reaction with set gypsum as a precursor. When set gypsum was immersed in a 100°C 1 mol/L Na3PO4 aqueous solution for 24 h, the set gypsum transformed into CO3Ap. Both CO3Ap and sintered hydroxyapatite (s-HAp), which was used as a control, were implanted into surgically created tibial bone defects of rats for histological evaluation. Two and 4 weeks after the implantation, histological sections were created and observed using light microscopy. The CO3Ap granules revealed both direct apposition of the bone matrix by osteoblasts and osteoclastic resorption. In contrast, the s-HAp granules maintained their contour even after 4 weeks following implantation which implied that there was a lack of replacement into the bone. The s-HAp granules were sometimes encapsulated with fibrous tissue, and macrophage polykaryon was occasionally observed directly apposed to the implanted granules. From the viewpoint of bone remodeling, the CO3Ap granules mimicked the bone matrix, suggesting that CO3Ap may be an appropriate bone substitute. Yasunori Ayukawa, Yumiko Suzuki, Kanji Tsuru, Kiyoshi Koyano, and Kunio Ishikawa Copyright © 2015 Yasunori Ayukawa et al. All rights reserved. Alginate/Poly(γ-glutamic Acid) Base Biocompatible Gel for Bone Tissue Engineering Sun, 04 Oct 2015 11:05:19 +0000 A technique for synthesizing biocompatible hydrogels by cross-linking calcium-form poly(γ-glutamic acid), alginate sodium, and Pluronic F-127 was created, in which alginate can be cross-linked by Ca2+ from Ca–γ-PGA directly and γ-PGA molecules introduced into the alginate matrix to provide pH sensitivity and hemostasis. Mechanical properties, swelling behavior, and blood compatibility were investigated for each hydrogel compared with alginate and for γ-PGA hydrogel with the sodium form only. Adding F-127 improves mechanical properties efficiently and influences the temperature-sensitive swelling of the hydrogels but also has a minor effect on pH-sensitive swelling and promotes anticoagulation. MG-63 cells were used to test biocompatibility. Gelation occurred gradually through change in the elastic modulus as the release of calcium ions increased over time and caused ionic cross-linking, which promotes the elasticity of gel. In addition, the growth of MG-63 cells in the gel reflected nontoxicity. These results showed that this biocompatible scaffold has potential for application in bone materials. Wing P. Chan, Fu-Chen Kung, Yu-Lin Kuo, Ming-Chen Yang, and Wen-Fu Thomas Lai Copyright © 2015 Wing P. Chan et al. All rights reserved. Potential of Newborn and Adult Stem Cells for the Production of Vascular Constructs Using the Living Tissue Sheet Approach Sun, 04 Oct 2015 10:13:54 +0000 Bypass surgeries using native vessels rely on the availability of autologous veins and arteries. An alternative to those vessels could be tissue-engineered vascular constructs made by self-organized tissue sheets. This paper intends to evaluate the potential use of mesenchymal stem cells (MSCs) isolated from two different sources: (1) bone marrow-derived MSCs and (2) umbilical cord blood-derived MSCs. When cultured in vitro, a proportion of those cells differentiated into smooth muscle cell- (SMC-) like cells and expressed contraction associated proteins. Moreover, these cells assembled into manipulable tissue sheets when cultured in presence of ascorbic acid. Tubular vessels were then produced by rolling those tissue sheets on a mandrel. The architecture, contractility, and mechanical resistance of reconstructed vessels were compared with tissue-engineered media and adventitia produced from SMCs and dermal fibroblasts, respectively. Histology revealed a collagenous extracellular matrix and the contractile responses measured for these vessels were stronger than dermal fibroblasts derived constructs although weaker than SMCs-derived constructs. The burst pressure of bone marrow-derived vessels was higher than SMCs-derived ones. These results reinforce the versatility of the self-organization approach since they demonstrate that it is possible to recapitulate a contractile media layer from MSCs without the need of exogenous scaffolding material. Jean-Michel Bourget, Robert Gauvin, David Duchesneau, Murielle Remy, François A. Auger, and Lucie Germain Copyright © 2015 Jean-Michel Bourget et al. All rights reserved. Titanium-Based Hip Stems with Drug Delivery Functionality through Additive Manufacturing Sun, 04 Oct 2015 09:23:58 +0000 Postoperative infections are a major concern in patients that receive implants. These infections generally occur in areas with poor blood flow and pathogens do not always respond to antibiotic treatment. With the latest developments in nanotechnology, the incorporation of antibiotics into prosthetic implants may soon become a standard procedure. The success will, however, depend on the ability to control the release of antibiotics at concentrations high enough to prevent the development of antibiotic-resistant strains. Through additive manufacturing, antibiotics can be incorporated into cementless femoral stems to produce prosthetic devices with antimicrobial properties. With the emerging increase in resistance to antibiotics, the incorporation of antimicrobial compounds other than antibiotics, preferably drugs with a broader spectrum of antimicrobial activity, will have to be explored. This review highlights the microorganisms associated with total hip arthroplasty (THA), discusses the advantages and disadvantages of the latest materials used in hip implants, compares different antimicrobial agents that could be incorporated, and addresses novel ideas for future research. Martin B. Bezuidenhout, Dimitar M. Dimitrov, Anton D. van Staden, Gert A. Oosthuizen, and Leon M. T. Dicks Copyright © 2015 Martin B. Bezuidenhout et al. All rights reserved. In Vitro Evaluation of Scaffolds for the Delivery of Mesenchymal Stem Cells to Wounds Sun, 04 Oct 2015 09:18:25 +0000 Mesenchymal stem cells (MSCs) have been shown to improve tissue regeneration in several preclinical and clinical trials. These cells have been used in combination with three-dimensional scaffolds as a promising approach in the field of regenerative medicine. We compare the behavior of human adipose-derived MSCs (AdMSCs) on four different biomaterials that are awaiting or have already received FDA approval to determine a suitable regenerative scaffold for delivering these cells to dermal wounds and increasing healing potential. AdMSCs were isolated, characterized, and seeded onto scaffolds based on chitosan, fibrin, bovine collagen, and decellularized porcine dermis. In vitro results demonstrated that the scaffolds strongly influence key parameters, such as seeding efficiency, cellular distribution, attachment, survival, metabolic activity, and paracrine release. Chick chorioallantoic membrane assays revealed that the scaffold composition similarly influences the angiogenic potential of AdMSCs in vivo. The wound healing potential of scaffolds increases by means of a synergistic relationship between AdMSCs and biomaterial resulting in the release of proangiogenic and cytokine factors, which is currently lacking when a scaffold alone is utilized. Furthermore, the methods used herein can be utilized to test other scaffold materials to increase their wound healing potential with AdMSCs. Elizabeth A. Wahl, Fernando A. Fierro, Thomas R. Peavy, Ursula Hopfner, Julian F. Dye, Hans-Günther Machens, José T. Egaña, and Thilo L. Schenck Copyright © 2015 Elizabeth A. Wahl et al. All rights reserved. Antimicrobial Activity Evaluation on Silver Doped Hydroxyapatite/Polydimethylsiloxane Composite Layer Sun, 04 Oct 2015 09:12:49 +0000 The goal of this study was the preparation, physicochemical characterization, and microbiological evaluation of novel hydroxyapatite doped with silver/polydimethylsiloxane (Ag:HAp-PDMS) composite layers. In the first stage, the deposition of polydimethylsiloxane (PDMS) polymer layer on commercially pure Si disks has been produced in atmospheric pressure corona discharges. Finally, the new silver doped hydroxyapatite/polydimethylsiloxane composite layer has been obtained by the thermal evaporation technique. The Ag:HAp-PDMS composite layers were characterized by various techniques, such as Scanning Electron Microscopy (SEM), Glow Discharge Optical Emission Spectroscopy (GDOES), and X-ray photoelectron spectroscopy (XPS). The antimicrobial activity of the Ag:HAp-PDMS composite layer was assessed against Candida albicans ATCC 10231 (ATCC—American Type Culture Collection) by culture based and confirmed by SEM and Confocal Laser Scanning Microscopy (CLSM) methods. This is the first study reporting the antimicrobial effect of the Ag:HAp-PDMS composite layer, which proved to be active against Candida albicans biofilm embedded cells. C. S. Ciobanu, A. Groza, S. L. Iconaru, C. L. Popa, P. Chapon, M. C. Chifiriuc, R. Hristu, G. A. Stanciu, C. C. Negrila, R. V. Ghita, M. Ganciu, and D. Predoi Copyright © 2015 C. S. Ciobanu et al. All rights reserved. Clinical Applications of S53P4 Bioactive Glass in Bone Healing and Osteomyelitic Treatment: A Literature Review Sun, 04 Oct 2015 09:09:38 +0000 Nowadays, S53P4 bioactive glass is indicated as a bone graft substitute in various clinical applications. This review provides an overview of the current published clinical results on indications such as craniofacial procedures, grafting of benign bone tumour defects, instrumental spondylodesis, and the treatment of osteomyelitis. Given the reported results that are based on examinations, such as clinical examinations by the surgeons, radiographs, CT, and MRI images, S53P4 bioactive glass may be beneficial in the various reported applications. Especially in craniofacial reconstructions like mastoid obliteration and orbital floor reconstructions, in grafting bone tumour defects, and in the treatment of osteomyelitis very promising results are obtained. Randomized clinical trials need to be performed in order to determine whether bioactive glass would be able to replace the current golden standard of autologous bone usage or with the use of antibiotic containing PMMA beads (in the case of osteomyelitis). N. A. P. van Gestel, J. Geurts, D. J. W. Hulsen, B. van Rietbergen, S. Hofmann, and J. J. Arts Copyright © 2015 N. A. P. van Gestel et al. All rights reserved. Effects of rhBMP-2 on Sandblasted and Acid Etched Titanium Implant Surfaces on Bone Regeneration and Osseointegration: Spilt-Mouth Designed Pilot Study Sun, 04 Oct 2015 08:42:16 +0000 This study was conducted to evaluate effects of rhBMP-2 applied at different concentrations to sandblasted and acid etched (SLA) implants on osseointegration and bone regeneration in a bone defect of beagle dogs as pilot study using split-mouth design. Methods. For experimental groups, SLA implants were coated with different concentrations of rhBMP-2 (0.1, 0.5, and 1 mg/mL). After assessment of surface characteristics and rhBMP-2 releasing profile, the experimental groups and untreated control groups (n = 6 in each group, two animals in each group) were placed in split-mouth designed animal models with buccal open defect. At 8 weeks after implant placement, implant stability quotients (ISQ) values were recorded and vertical bone height (VBH, mm), bone-to-implant contact ratio (BIC, %), and bone volume (BV, %) in the upper 3 mm defect areas were measured. Results. The ISQ values were highest in the 1.0 group. Mean values of VBH (mm), BIC (%), and BV (%) were greater in the 0.5 mg/mL and 1.0 mg/mL groups than those in 0.1 and control groups in buccal defect areas. Conclusion. In the open defect area surrounding the SLA implant, coating with 0.5 and 1.0 mg/mL concentrations of rhBMP-2 was more effective, compared with untreated group, in promoting bone regeneration and osseointegration. Nam-Ho Kim, So-Hyoun Lee, Jae-Jun Ryu, Kyung-Hee Choi, and Jung-Bo Huh Copyright © 2015 Nam-Ho Kim et al. All rights reserved. Anodisation Increases Integration of Unloaded Titanium Implants in Sheep Mandible Tue, 08 Sep 2015 13:27:12 +0000 Spark discharge anodic oxidation forms porous TiO2 films on titanium implant surfaces. This increases surface roughness and concentration of calcium and phosphate ions and may enhance early osseointegration. To test this, forty 3.75 mm × 13 mm titanium implants (Megagen, Korea) were placed into healed mandibular postextraction ridges of 10 sheep. There were 10 implants per group: RBM surface (control), RBM + anodised, RBM + anodised + fluoride, and titanium alloy + anodised surface. Resonant frequency analysis (RFA) was measured in implant stability quotient (ISQ) at surgery and at sacrifice after 1-month unloaded healing. Mean bone-implant contact (% BIC) was measured in undemineralised ground sections for the best three consecutive threads. One of 40 implants showed evidence of failure. RFA differed between groups at surgery but not after 1 month. RFA values increased nonsignificantly for all implants after 1 month, except for controls. There was a marked difference in BIC after 1-month healing, with higher values for alloy implants, followed by anodised + fluoride and anodised implants. Anodisation increased early osseointegration of rough-surfaced implants by 50–80%. RFA testing lacked sufficient resolution to detect this improvement. Whether this gain in early bone-implant contact is clinically significant is the subject of future experiments. Warwick J. Duncan, Min-Ho Lee, Tae-Sung Bae, Sook-Jeong Lee, Jennifer Gay, and Carolina Loch Copyright © 2015 Warwick J. Duncan et al. All rights reserved. Efficacy Study of Broken Rice Maltodextrin in In Vitro Wound Healing Assay Tue, 08 Sep 2015 13:06:25 +0000 Maltodextrins that contain both simple sugars and polymers of saccharides have been widely used as ingredients in food products and pharmaceutical delivery systems. To date, no much work has been reported on the applications of maltodextrin from broken rice (RB) sources. Therefore, the objective of this work was to investigate the in vitro wound healing efficacy of RB maltodextrin at different conditions. Wounds treated with lower dextrose equivalent (DE) range (DE 10–14) of maltodextrins at a concentration of 10% obtained from RB were found to be able to heal the wounds significantly faster () than maltodextrin with higher DE ranges (DE 15–19 and DE 20–24) and concentrations of 5% and 20%. The findings from both BrdU and MTT assay further confirmed its wound healing properties as the NIH 3T3 fibroblast wounded cells were able to proliferate without causing cytotoxic effect when wounded cell was treated with maltodextrin. All these findings indicated that the RB maltodextrin could perform better than the commercial maltodextrin at the same DE range. This study showed that RB maltodextrins had better functionality properties than other maltodextrin sources and played a beneficial role in wound healing application. Zahiah Mohamed Amin, Soo Peng Koh, Swee Keong Yeap, Nur Syazwani Abdul Hamid, Chin Ping Tan, and Kamariah Long Copyright © 2015 Zahiah Mohamed Amin et al. All rights reserved. The Effect of Covalently Immobilized FGF-2 on Biphasic Calcium Phosphate Bone Substitute on Enhanced Biological Compatibility and Activity Mon, 07 Sep 2015 09:55:24 +0000 The purpose of this research was to covalently graft fibroblast growth factor 2 (FGF-2) onto biphasic calcium phosphate (BCP) via a bifunctional cross-linker technique and to estimate the optimal dose of FGF-2 resulting in the best osteogenic differentiation of human mesenchymal stem cells (hMSCs). SEM observation revealed that the surface of the 100 ng FGF-2 coated BCP was completely covered with the nanoparticles expected to be from the silane coupling agent. XRD, FT-IR, and XPS analysis showed that silane treatment, bifunctional cross-linker coating, and FGF-2 covalent grafts were conducted successfully without deforming the crystalline structure of BCP. An MTT assay demonstrated that FGF-2 coated BCP had good biocompatibility, regardless of the concentration of FGF-2, after 24 or 48 h of incubation. An alkaline phosphatase (ALP) activity assay (14 days of incubation) and the ALP gene expression level of real-time PCR analysis (7 days of incubation) revealed that 50, 100, and 200 ng FGF-2 coated BCP induced the highest activities among all experimental groups and control group (). Thus, low concentrations of FGF-2 facilitated excellent osteogenesis and were effective at enhancing osteogenic potential. Also, the bifunctional cross-linker technique is expected to be a more feasible way to induce osteogenic differentiation while minimizing the risk of FGF-2 overdose. Kyung-Suk Moon, Eun-Joo Choi, Seunghan Oh, and Sungtae Kim Copyright © 2015 Kyung-Suk Moon et al. All rights reserved. Efficacy of Biodentine as an Apical Plug in Nonvital Permanent Teeth with Open Apices: An In Vitro Study Mon, 07 Sep 2015 09:44:31 +0000 The aim of this study was to evaluate the apical microleakage of Biodentine and MTA orthograde apical plugs and to compare the effect of thickness of these biomaterials on their sealing ability. A total of eighty maxillary anterior teeth were used. The apices were removed by cutting with a diamond disc (Jota, Germany) 2 mm from the apical root end in an attempt to standardize the working length of all specimens to 15 ± 1 mm. Both materials were placed in 1–4 mm thickness as apical plugs root canal. Root canal leakage was evaluated by the fluid filtration technique. One-way ANOVA was used in order to determine normality of dispersal distribution of parameters; thereafter, results were analyzed by Kolmogorov-Smirnov test. Overall, between microleakage values of MTA and Biodentine regardless of apical plug thickness, no difference was observed. In terms of plug thickness, a statistically significant difference was observed between the subgroups of MTA and Biodentine (). The apical sealing ability of Biodentine was comparable to MTA at any apical plug thickness. Mehmet Bani, Elif Sungurtekin-Ekçi, and Mesut Enes Odabaş Copyright © 2015 Mehmet Bani et al. All rights reserved. Surface Modifications and Their Effects on Titanium Dental Implants Mon, 07 Sep 2015 09:39:38 +0000 This review covers several basic methodologies of surface treatment and their effects on titanium (Ti) implants. The importance of each treatment and its effects will be discussed in detail in order to compare their effectiveness in promoting osseointegration. Published literature for the last 18 years was selected with the use of keywords like titanium dental implant, surface roughness, coating, and osseointegration. Significant surface roughness played an important role in providing effective surface for bone implant contact, cell proliferation, and removal torque, despite having good mechanical properties. Overall, published studies indicated that an acid etched surface-modified and a coating application on commercial pure titanium implant was most preferable in producing the good surface roughness. Thus, a combination of a good surface roughness and mechanical properties of titanium could lead to successful dental implants. A. Jemat, M. J. Ghazali, M. Razali, and Y. Otsuka Copyright © 2015 A. Jemat et al. All rights reserved. Cholesteryl Pullulan Encapsulated TNF-α Nanoparticles Are an Effective Mucosal Vaccine Adjuvant against Influenza Virus Tue, 01 Sep 2015 06:12:31 +0000 We encapsulated tumor necrosis factor-α (TNF-α), a major proinflammatory cytokine, into cholesteryl pullulan (CHP) to prepare TNF/CHP nanoparticles. In this report, we describe the immune-enhancing capability of the nanoparticles to act as a vaccine adjuvant. TNF/CHP nanoparticles showed excellent storage stability and enhanced host immune responses to external immunogens. The nanoparticles were effective via the nasal route of administration for inducing systemic IgG1 as well as mucosal IgA. We applied the nanoparticles in a model experimental influenza virus infection to investigate their adjuvant ability. TNF/CHP nanoparticles combined with a conventional split vaccine protected mice via nasal administration against a lethal challenge of A/PR/8/34 (H1N1) influenza virus. Mechanistic studies showed that the nanoparticles enhanced antigen uptake by dendritic cells (DCs) and moderately induced the expression of inflammation-related genes in nasopharynx lymphoid tissue (NALT), leading to the activation of both B and T cells. Preliminary safety study revealed no severe toxicity to TNF/CHP nanoparticles. Slight-to-moderate influences in nasal mucosa were observed only in the repeated administration and they seemed to be reversible. Our data show that TNF/CHP nanoparticles effectively enhance both humoral and cellular immunity and could be a potential adjuvant for vaccines against infectious diseases, especially in the mucosa. Daiki Nagatomo, Madoka Taniai, Harumi Ariyasu, Mutsuko Taniguchi, Miho Aga, Toshio Ariyasu, Tsunetaka Ohta, and Shigeharu Fukuda Copyright © 2015 Daiki Nagatomo et al. All rights reserved. Corrigendum to “Characterization of Bone Marrow Mononuclear Cells on Biomaterials for Bone Tissue Engineering In Vitro” Mon, 31 Aug 2015 12:02:36 +0000 Dirk Henrich, René Verboket, Alexander Schaible, Kerstin Kontradowitz, Elsie Oppermann, Jan C. Brune, Christoph Nau, Simon Meier, Halvard Bonig, Ingo Marzi, and Caroline Seebach Copyright © 2015 Dirk Henrich et al. All rights reserved. In Vitro and In Vivo Response to Low-Modulus PMMA-Based Bone Cement Thu, 20 Aug 2015 16:17:29 +0000 The high stiffness of acrylic bone cements has been hypothesized to contribute to the increased number of fractures encountered after vertebroplasty, which has led to the development of low-modulus cements. However, there is no data available on the in vivo biocompatibility of any low-modulus cement. In this study, the in vitro cytotoxicity and in vivo biocompatibility of two types of low-modulus acrylic cements, one modified with castor oil and one with linoleic acid, were evaluated using human osteoblast-like cells and a rodent model, respectively. While the in vitro cytotoxicity appeared somewhat affected by the castor oil and linoleic acid additions, no difference could be found in the in vivo response to these cements in comparison to the base, commercially available cement, in terms of histology and flow cytometry analysis of the presence of immune cells. Furthermore, the in vivo radiopacity of the cements appeared unaltered. While these results are promising, the mechanical behavior of these cements in vivo remains to be investigated. Elin Carlsson, Gemma Mestres, Kiatnida Treerattrakoon, Alejandro López, Marjam Karlsson Ott, Sune Larsson, and Cecilia Persson Copyright © 2015 Elin Carlsson et al. All rights reserved. Synthesis and Properties of pH-, Thermo-, and Salt-Sensitive Modified Poly(aspartic acid)/Poly(vinyl alcohol) IPN Hydrogel and Its Drug Controlled Release Thu, 13 Aug 2015 14:00:08 +0000 Modified poly(aspartic acid)/poly(vinyl alcohol) interpenetrating polymer network (KPAsp/PVA IPN) hydrogel for drug controlled release was synthesized by a simple one-step method in aqueous system using poly(aspartic acid) grafting 3-aminopropyltriethoxysilane (KH-550) and poly(vinyl alcohol) (PVA) as materials. The hydrogel surface morphology and composition were characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The thermal stability was analyzed by thermogravimetric analysis (TGA). The swelling properties and pH, temperature, and salt sensitivities of KPAsp, KPAsp/PVA semi-interpenetrating polymer network (semi-IPN), and KPAsp/PVA IPN hydrogels were also investigated. All of the three hydrogels showed ampholytic pH-responsive properties, and swelling behavior was also extremely sensitive to the temperature, ionic strength, and cationic species. Finally, the drug controlled release properties of the three hydrogels were evaluated and results indicated that three hydrogels could control drug release by external surroundings stimuli. The drug controlled release properties of KPAsp/PVA IPN hydrogel are the most outstanding, and the correlative measured release profiles of salicylic acid at 37°C were 32.6 wt% at pH = 1.2 (simulated gastric fluid) and 62.5 wt% at pH = 7.4 (simulated intestinal fluid), respectively. These results indicated that KPAsp/PVA IPN hydrogels are a promising carrier system for controlled drug delivery. Jingqiong Lu, Yinhui Li, Deng Hu, Xiaoling Chen, Yongmei Liu, Liping Wang, and Yansheng Zhao Copyright © 2015 Jingqiong Lu et al. All rights reserved. Research Advances in Tissue Engineering Materials for Sustained Release of Growth Factors Tue, 11 Aug 2015 05:50:26 +0000 Growth factors are a class of cytokines that stimulate cell growth and are widely used in clinical practice, such as wound healing, revascularization, bone repair, and nervous system disease. However, free growth factors have a short half-life and are instable in vivo. Therefore, the search of excellent carriers to enhance sustained release of growth factors in vivo has become an area of intense research interest. The development of controlled-release systems that protect the recombinant growth factors from enzymatic degradation and provide sustained delivery at the injury site during healing should enhance the growth factor’s application in tissue regeneration. Thus, this study reviews current research on commonly used carriers for sustained release of growth factors and their sustained release effects for preservation of their bioactivity and their accomplishment in tissue engineering approaches. Hai-yang Zhao, Jiang Wu, Jing-jing Zhu, Ze-cong Xiao, Chao-chao He, Hong-xue Shi, Xiao-kun Li, Shu-lin Yang, and Jian Xiao Copyright © 2015 Hai-yang Zhao et al. All rights reserved. Erratum to “Localized and Sustained Delivery of Erythropoietin from PLGA Microspheres Promotes Functional Recovery and Nerve Regeneration in Peripheral Nerve Injury” Tue, 28 Jul 2015 11:22:45 +0000 Wei Zhang, Yuan Gao, Yan Zhou, Jianheng Liu, Licheng Zhang, Anhua Long, Lihai Zhang, and Peifu Tang Copyright © 2015 Wei Zhang et al. All rights reserved. New Biomaterials and Regenerative Medicine Strategies in Periodontology, Oral Surgery, Esthetic and Implant Dentistry Mon, 27 Jul 2015 15:01:11 +0000 David M. Dohan Ehrenfest, Hom-Lay Wang, Jean-Pierre Bernard, and Gilberto Sammartino Copyright © 2015 David M. Dohan Ehrenfest et al. All rights reserved. Histological and Histomorphometric Human Results of HA-Beta-TCP 30/70 Compared to Three Different Biomaterials in Maxillary Sinus Augmentation at 6 Months: A Preliminary Report Sun, 26 Jul 2015 13:04:59 +0000 Objective. The aim of this investigation was to examine the bone regenerative potential of newly biphasic calcium phosphate ceramics (HA-β-TCP 30/70), by assessing histological and histomorphometric results of human specimens retrieved from sinuses augmented with HA-β-TCP 30/70, and comparing them to anorganic bovine bone (ABB), mineralized solvent-dehydrated bone allograft (MSDBA), and equine bone (EB), after a healing period of 6 months. Materials and Methods. Four consecutive patients with edentulous atrophic posterior maxilla were included in this report. A two-stage procedure was carried out for sinus augmentation with HA-β-TCP 30/70, ABB, MSDBA, and EB. After 6 months, specimens were retrieved at the time of implant placement and processed for histological and histomorphometric analyses. Results. At histological examination, all biomaterials were in close contact with the newly formed bone and showed the same pattern of bone formation; the grafted granules were surrounded by a bridge-like network of newly formed bone. A limited number of ABB particles were partially covered by connective tissue. The histomorphometric analysis revealed 30.2% newly formed bone for Ha-β-TCP 30/70, 20.1% for ABB, 16.4% for MSDBA, and 21.9% for EB. Conclusions. Within the limitations of the present investigation, these results support the successful use of HA-β-TCP 30/70 for sinus augmentation. Susanna Annibali, Giovanna Iezzi, Gian Luca Sfasciotti, Maria Paola Cristalli, Iole Vozza, Carlo Mangano, Gerardo La Monaca, and Antonella Polimeni Copyright © 2015 Susanna Annibali et al. All rights reserved. Oral Streptococci Biofilm Formation on Different Implant Surface Topographies Sun, 26 Jul 2015 08:47:31 +0000 The establishment of the subgingival microbiota is dependent on successive colonization of the implant surface by bacterial species. Different implant surface topographies could influence the bacterial adsorption and therefore jeopardize the implant survival. This study evaluated the biofilm formation capacity of five oral streptococci species on two titanium surface topographies. In vitro biofilm formation was induced on 30 titanium discs divided in two groups: sandblasted acid-etched (SAE- ) and as-machined (M- ) surface. The specimens were immersed in sterilized whole human unstimulated saliva and then in fresh bacterial culture with five oral streptococci species: Streptococcus sanguinis, Streptococcus salivarius, Streptococcus mutans, Streptococcus sobrinus, and Streptococcus cricetus. The specimens were fixed and stained and the adsorbed dye was measured. Surface characterization was performed by atomic force and scanning electron microscopy. Surface and microbiologic data were analyzed by Student’s -test and two-way ANOVA, respectively (). S. cricetus, S. mutans, and S. sobrinus exhibited higher biofilm formation and no differences were observed between surfaces analyzed within each species (). S. sanguinis exhibited similar behavior to form biofilm on both implant surface topographies, while S. salivarius showed the lowest ability to form biofilm. It was concluded that biofilm formation on titanium surfaces depends on surface topography and species involved. Pedro Paulo Cardoso Pita, José Augusto Rodrigues, Claudia Ota-Tsuzuki, Tatiane Ferreira Miato, Elton G. Zenobio, Gabriela Giro, Luciene C. Figueiredo, Cristiane Gonçalves, Sergio A. Gehrke, Alessandra Cassoni, and Jamil Awad Shibli Copyright © 2015 Pedro Paulo Cardoso Pita et al. All rights reserved. Influence of Leukocyte- and Platelet-Rich Fibrin (L-PRF) in the Healing of Simple Postextraction Sockets: A Split-Mouth Study Sun, 26 Jul 2015 08:17:48 +0000 The aim of this study was to evaluate the effects of leukocyte- and platelet-rich fibrin (L-PRF) on the pain and soft tissue healing after tooth extractions. Twenty-six patients (9 males and 17 females) were treated with multiple extractions (2 to 8), with a total of 108 extractions. This was an exploratory single blinded randomized clinical trial with a split-mouth design. The pain after the surgery was assessed in each patient by the VAS scale (1 to 10) at intervals of 24-48-72-96 hours. The soft tissue healing was clinically evaluated at 3, 7, 14, and 21 days after surgery by the same examiner surgeon, using the modified Healing Index (4 to 12). The mean value of postextraction pain was 3.2 ± 0.3 in the experimental sides and 4.1 ± 0.1 in the control sides. After 7 days from the extractions, the values of modified Healing Index in the experimental and control groups were, respectively, 4.8 ± 0.6 and 5.1 ± 0.9. The use of L-PRF in postextraction sockets filling can be proposed as a useful procedure in order to manage the postoperative pain and to promote the soft tissue healing process, reducing the early adverse effects of the inflammation. Gaetano Marenzi, Francesco Riccitiello, Mariano Tia, Alessandro di Lauro, and Gilberto Sammartino Copyright © 2015 Gaetano Marenzi et al. All rights reserved. Innate Immunity and Biomaterials at the Nexus: Friends or Foes Sun, 12 Jul 2015 11:12:45 +0000 Biomaterial implants are an established part of medical practice, encompassing a broad range of devices that widely differ in function and structural composition. However, one common property amongst biomaterials is the induction of the foreign body response: an acute sterile inflammatory reaction which overlaps with tissue vascularisation and remodelling and ultimately fibrotic encapsulation of the biomaterial to prevent further interaction with host tissue. Severity and clinical manifestation of the biomaterial-induced foreign body response are different for each biomaterial, with cases of incompatibility often associated with loss of function. However, unravelling the mechanisms that progress to the formation of the fibrotic capsule highlights the tightly intertwined nature of immunological responses to a seemingly noncanonical “antigen.” In this review, we detail the pathways associated with the foreign body response and describe possible mechanisms of immune involvement that can be targeted. We also discuss methods of modulating the immune response by altering the physiochemical surface properties of the biomaterial prior to implantation. Developments in these areas are reliant on reproducible and effective animal models and may allow a “combined” immunomodulatory approach of adapting surface properties of biomaterials, as well as treating key immune pathways to ultimately reduce the negative consequences of biomaterial implantation. Susan N. Christo, Kerrilyn R. Diener, Akash Bachhuka, Krasimir Vasilev, and John D. Hayball Copyright © 2015 Susan N. Christo et al. All rights reserved. Nanostructures Control the Hepatocellular Responses to a Cytotoxic Agent “Cisplatin” Sun, 12 Jul 2015 10:53:32 +0000 In drug discovery programs, the alteration between in vivo and in vitro cellular responses to drug represents one of the main challenges. Since the variation in the native extracellular matrix (ECM) between in vivo and 2D in vitro conditions is one of the key reasons for such discrepancies, thus the utilization of substrate that likely mimics ECM characteristics (topography, stiffness, and chemical composition) is needed to overcome such problem. Here, we investigated the role of substrate nanotopography as one of the major determinants of hepatic cellular responses to a chemotherapeutic agent “cisplatin.” We studied the substratum induced variations in cisplatin cytotoxicity; a higher cytotoxic response to cisplatin was observed for cells cultured on the nanopattern relative to a flat substrate. Moreover, the nanofeatures with grating shapes that mimic the topography of major ECM protein constituents (collagen) induced alterations in the cellular orientation and chromatin condensation compared to flat surfaces. Accordingly, the developments of biomimetic substrates with a particular topography could have potentials in drug development analyses to reflect more physiological mimicry conditions in vitro. Shimaa A. Abdellatef, Riho Tange, Takeshi Sato, Akihiko Ohi, Toshihide Nabatame, and Akiyoshi Taniguchi Copyright © 2015 Shimaa A. Abdellatef et al. All rights reserved. Gold Nanoparticles Promote Oxidant-Mediated Activation of NF-κB and 53BP1 Recruitment-Based Adaptive Response in Human Astrocytes Tue, 23 Jun 2015 13:31:42 +0000 Nanogold-based materials are promising candidate tools for nanobased medicine. Nevertheless, no conclusive information on their cytotoxicity is available. In the present study, we investigated the effects of gold nanoparticles (AuNPs) on human astrocytes in vitro. Nanogold treatment in a wide range of concentrations did not result in cytotoxicity. In contrast, nanogold provoked changes in the astrocyte cell cycle and induced senescence-associated β-galactosidase activity. AuNPs promoted oxidative stress and caused activation of NF-κB pathway. After nanogold treatment, an inverse correlation between the formation of 53BP1 foci and micronuclei generation was observed. The robust 53BP1 recruitment resulted in reduced micronuclei production. Thus, nanogold treatment stimulated an adaptive response in a human astrocyte cell. Jennifer Mytych, Anna Lewinska, Jacek Zebrowski, and Maciej Wnuk Copyright © 2015 Jennifer Mytych et al. All rights reserved. Dental Stem Cell Migration on Pulp Ceiling Cavities Filled with MTA, Dentin Chips, or Bio-Oss Wed, 03 Jun 2015 08:03:51 +0000 MTA, Bio-Oss, and dentin chips have been successfully used in endodontics. The aim of this study was to assess the adhesion and migration of dental stem cells on human pulp ceiling cavities filled with these endodontic materials in an experimental model, which mimics the clinical conditions of regenerative endodontics. Cavities were formed, by a homemade mold, on untouched third molars, filled with endodontic materials, and observed with electron microscopy. Cells were seeded on cavities’ surface and their morphology and number were analysed. The phenomenon of tropism was assessed in a migration assay. All three materials demonstrated appropriate microstructures for cell attachment. Cells grew on all reagents, but they showed a differential morphology. Moreover, variations were observed when comparing cells numbers on cavity’s filling versus the surrounding dentine disc. The highest number of cells was recorded on dentin chips whereas the opposite was true for Bio-Oss. This was confirmed in the migration assay where a statistically significant lower number of cells migrated towards Bio-Oss as compared to MTA and dentin chips. This study highlights that MTA and dentin chips have a greater potential compared to Bio-Oss regarding the attraction of dental stem cells and are good candidates for bioengineered pulp regeneration. Stefania Lymperi, Vasiliki Taraslia, Ioannis N. Tsatsoulis, Athina Samara, Athanasios D. Velentzas, Anastasia Agrafioti, Ema Anastasiadou, and Evangelos Kontakiotis Copyright © 2015 Stefania Lymperi et al. All rights reserved. A Novel Injectable Magnesium/Calcium Sulfate Hemihydrate Composite Cement for Bone Regeneration Sun, 31 May 2015 11:37:51 +0000 Objective. A novel injectable magnesium/calcium sulfate hemihydrate (Mg/CSH) composite with improved properties was reported here. Methods. Composition, setting time, injectability, compressive strength, and bioactivity in simulated body fluid (SBF) of the Mg/CSH composite were evaluated. Furthermore, the cellular responses of canine bone marrow stromal cells (cBMSCs) and bone formation capacity after the implantation of Mg/CSH in tibia defects of canine were investigated. Results. Mg/CSH possessed a prolonged setting time and markedly improved injectability and mechanical property . Mg/CSH samples showed better degradability than CSH in SBF after 21 days of soaking . Moreover, the degrees of cell attachment, proliferation, and capability of osteogenic differentiation on the Mg/CSH specimens were higher than those on CSH, without significant cytotoxicity and with the increased proliferation index, ALP activity, and expression levels of integrin β1 and Coll I in cBMSCs . Mg/CSH enhanced the efficiency of new bone formation at the tibia defect area, including the significantly elevated bone mineral density, bone area fraction, and Coll I expression level . Conclusions. The results implied that this new injectable bone scaffold exhibited promising prospects for bone repair and had a great potential in bone tissue engineering. Shanchuan Zhang, Ke Yang, Fuzhai Cui, Yi Jiang, Lingling E, Baohua Xu, and Hongchen Liu Copyright © 2015 Shanchuan Zhang et al. All rights reserved. The Use of Natural Polysaccharides as Biomaterials Mon, 25 May 2015 08:53:48 +0000 Paola Laurienzo, João C. Fernandes, Sylvia Colliec-Jouault, and J. Helen Fitton Copyright © 2015 Paola Laurienzo et al. All rights reserved. Prevention of Polyglycolic Acid-Induced Peritoneal Adhesions Using Alginate in a Rat Model Thu, 21 May 2015 14:18:05 +0000 Postoperative intra-abdominal or intrathoracic adhesions sometimes cause significant morbidity. We have designed three types of alginate-based treatments using strongly cross-linked (SL), weakly cross-linked (WL), and non-cross-linked (NL) alginate with calcium gluconate. In rat experiments, we compared the antiadhesive effects of the three types of alginate-based treatments, fibrin glue treatment (a standard treatment), and no treatment against adhesions caused by polyglycolic acid (PGA) mesh (PGA-induced adhesions). The antiadhesive materials were set on the PGA sheet fixed on the parietal peritoneum of the abdomen. Fifty-six days later, the adhesions were evaluated macroscopically by the adhesion scores and microscopically by hematoxylin-eosin staining and immunostaining. We also tested the fibroblast growth on the surface of the antiadhesive materials in vitro. The antiadhesive effects of WL and NL were superior to the no treatment and fibrin glue treatment. A microscopic evaluation confirmed that the PGA sheet was covered by a peritoneal layer constructed of well-differentiated mesothelial cells, and the inflammation was most improved in the NL and WL. The fibroblast growth was inhibited most on the surfaces of the NL and WL. These results suggest that either the WL or NL treatments are suitable for preventing PGA-induced adhesions compared to SL or the conventional treatment. Mari Matoba, Ayumi Hashimoto, Ayumi Tanzawa, Taichi Orikasa, Junki Ikeda, Yoshizumi Iwame, Yuki Ozamoto, Rie Abe, Hiroe Miyamoto, Chiko Yoshida, Toru Hashimoto, Hiroko Torii, Hideki Takamori, Shinichiro Morita, Hiroyuki Tsujimoto, and Akeo Hagiwara Copyright © 2015 Mari Matoba et al. All rights reserved. Insights in Behavior of Variably Formulated Alginate-Based Microcapsules for Cell Transplantation Wed, 20 May 2015 10:00:35 +0000 Alginate-based microencapsulation of live cells may offer the opportunity to treat chronic and degenerative disorders. So far, a thorough assessment of physical-chemical behavior of alginate-based microbeads remains cloudy. A disputed issue is which divalent cation to choose for a high performing alginate gelling process. Having selected, in our system, high mannuronic (M) enriched alginates, we studied different gelling cations and their combinations to determine their eventual influence on physical-chemical properties of the final microcapsules preparation, in vitro and in vivo. We have shown that used of ultrapure alginate allows for high biocompatibility of the formed microcapsules, regardless of gelation agents, while use of different gelling cations is associated with corresponding variable effects on the capsules’ basic architecture, as originally reported in this work. However, only the final application which the capsules are destined to will ultimately guide the selection of the ideal, specific gelling divalent cations, since in principle there are no capsules that are better than others. Pia Montanucci, Silvia Terenzi, Claudio Santi, Ilaria Pennoni, Vittorio Bini, Teresa Pescara, Giuseppe Basta, and Riccardo Calafiore Copyright © 2015 Pia Montanucci et al. All rights reserved. Preparation of Porous Chitosan-Siloxane Hybrids Coated with Hydroxyapatite Particles Wed, 20 May 2015 08:07:02 +0000 This paper describes the apatite deposition of chitosan-silicate porous hybrids derived from chitosan and γ-glycidoxypropyltrimethoxysilane (GPTMS) in alkaline phosphate solution. The preparation of porous hybrids with needle-like apatite on their surfaces is described. Following apatite deposition the porous hybrids maintained high porosity. The enzymatic degradation rate was low even after 6 months and the porous hybrids were very flexible and cut easily using surgical scissors. Yuki Shirosaki, Kohei Okamoto, Satoshi Hayakawa, Akiyoshi Osaka, and Takuji Asano Copyright © 2015 Yuki Shirosaki et al. All rights reserved. Preliminary Study on Biosynthesis of Bacterial Nanocellulose Tubes in a Novel Double-Silicone-Tube Bioreactor for Potential Vascular Prosthesis Tue, 19 May 2015 14:30:38 +0000 Bacterial nanocellulose (BNC) has demonstrated a tempting prospect for applications in substitute of small blood vessels. However, present technology is inefficient in production and BNC tubes have a layered structure that may bring danger after implanting. Double oxygen-permeable silicone tubes in different diameters were therefore used as a tube-shape mold and also as oxygenated supports to construct a novel bioreactor for production of the tubular BNC materials. Double cannula technology was used to produce tubular BNC via cultivations with Acetobacter xylinum, and Kombucha, a symbiosis of acetic acid bacteria and yeasts. The results indicated that Kombucha gave higher yield and productivity of BNC than A. xylinum. Bacterial nanocellulose was simultaneously synthesized both on the inner surface of the outer silicone tube and on the outer surface of the inner silicone tube. Finally, the nano BNC fibrils from two directions formed a BNC tube with good structural integrity. Scanning electron microscopy inspection showed that the tubular BNC had a multilayer structure in the beginning but finally it disappeared and an intact BNC tube formed. The mechanical properties of BNC tubes were comparable with the reported value in literatures, demonstrating a great potential in vascular implants or in functional substitutes in biomedicine. Feng Hong, Bin Wei, and Lin Chen Copyright © 2015 Feng Hong et al. All rights reserved. Polysaccharide-Coated Magnetic Nanoparticles for Imaging and Gene Therapy Tue, 19 May 2015 13:59:23 +0000 Today, nanotechnology plays a vital role in biomedical applications, especially for the diagnosis and treatment of various diseases. Among the many different types of fabricated nanoparticles, magnetic metal oxide nanoparticles stand out as unique and useful tools for biomedical applications, because of their imaging characteristics and therapeutic properties such as drug and gene carriers. Polymer-coated magnetic particles are currently of particular interest to investigators in the fields of nanobiomedicine and fundamental biomaterials. Theranostic magnetic nanoparticles that are encapsulated or coated with polymers not only exhibit imaging properties in response to stimuli, but also can efficiently deliver various drugs and therapeutic genes. Even though a large number of polymer-coated magnetic nanoparticles have been fabricated over the last decade, most of these have only been used for imaging purposes. The focus of this review is on polysaccharide-coated magnetic nanoparticles used for imaging and gene delivery. Saji Uthaman, Sang Joon Lee, Kondareddy Cherukula, Chong-Su Cho, and In-Kyu Park Copyright © 2015 Saji Uthaman et al. All rights reserved. Recombinant Phage Coated 1D Al2O3 Nanostructures for Controlling the Adhesion and Proliferation of Endothelial Cells Tue, 19 May 2015 13:48:34 +0000 A novel synthesis of a nanostructured cell adhesive surface is investigated for future stent developments. One-dimensional (1D) Al2O3 nanostructures were prepared by chemical vapor deposition of a single source precursor. Afterwards, recombinant filamentous bacteriophages which display a short binding motif with a cell adhesive peptide (RGD) on p3 and p8 proteins were immobilized on these 1D Al2O3 nanostructures by a simple dip-coating process to study the cellular response of human endothelial EA hy.926. While the cell density decreased on as-deposited 1D Al2O3 nanostructures, we observed enhanced cell proliferation and cell-cell interaction on recombinant phage overcoated 1D Al2O3 nanostructures. The recombinant phage overcoating also supports an isotropic cell spreading rather than elongated cell morphology as we observed on as-deposited Al2O3 1D nanostructures. Juseok Lee, Hojeong Jeon, Ayman Haidar, Hashim Abdul-Khaliq, Michael Veith, Cenk Aktas, and Youngjun Kim Copyright © 2015 Juseok Lee et al. All rights reserved. A Direct Sulfation Process of a Marine Polysaccharide in Ionic Liquid Tue, 19 May 2015 13:43:45 +0000 GY785 is an exopolysaccharide produced by a mesophilic bacterial strain Alteromonas infernus discovered in the deep-sea hydrothermal vents. GY785 highly sulfated derivative (GY785 DRS) was previously demonstrated to be a promising molecule driving the efficient mesenchymal stem cell chondrogenesis for cartilage repair. This glycosaminoglycan- (GAG-) like compound was modified in a classical solvent (N,N′-dimethylformamide). However, the use of classical solvents limits the polysaccharide solubility and causes the backbone degradation. In the present study, a one-step efficient sulfation process devoid of side effects (e.g., polysaccharide depolymerization and/or degradation) was developed to produce GAG-like derivatives. The sulfation of GY785 derivative (GY785 DR) was carried out using ionic liquid as a reaction medium. The successful sulfation of this anionic and highly branched heteropolysaccharide performed in ionic liquid would facilitate the production of new molecules of high specificity for biological targets such as tissue engineering or regenerative medicine. Nathalie Chopin, Corinne Sinquin, Jacqueline Ratiskol, Agata Zykwinska, Pierre Weiss, Stéphane Cérantola, Jean Le Bideau, and Sylvia Colliec-Jouault Copyright © 2015 Nathalie Chopin et al. All rights reserved. Comparison and Characterisation of Regenerated Chitosan from 1-Butyl-3-methylimidazolium Chloride and Chitosan from Crab Shells Tue, 19 May 2015 13:37:27 +0000 Chitosan is a biopolymer derived from chitin which is naturally occurring in the exoskeleton of crustaceans. This paper reports dissolution and regeneration of chitosan by directly dissolving in an ionic liquid solvent, 1-butyl-3-methylimidazolium chloride (BMIMCl). This will provide an ideal platform to solubilise these kinds of polymers to achieve the dissolution. The current study dissolved chitosan from crab shell utilising BMIMCl as a solvent and characterised the resultant regenerated polymer. The regenerated chitosan showed increased hydrogen bonding when characterised by Fourier transform infrared (FTIR) spectral analysis. In addition, the study also compared the characteristics of regenerated and generic chitosan. The regenerated chitosan was also evaluated for antimicrobial properties and showed to possess antibacterial features similar to the commercial grade. This method can be utilised in future for blending of polymers with chitosan in a dissolved phase. Saniyat Islam, Lyndon Arnold, and Rajiv Padhye Copyright © 2015 Saniyat Islam et al. All rights reserved. 3D Bioprinting of Carboxymethylated-Periodate Oxidized Nanocellulose Constructs for Wound Dressing Applications Tue, 19 May 2015 13:35:35 +0000 Nanocellulose has a variety of advantages, which make the material most suitable for use in biomedical devices such as wound dressings. The material is strong, allows for production of transparent films, provides a moist wound healing environment, and can form elastic gels with bioresponsive characteristics. In this study, we explore the application of nanocellulose as a bioink for modifying film surfaces by a bioprinting process. Two different nanocelluloses were used, prepared with TEMPO mediated oxidation and a combination of carboxymethylation and periodate oxidation. The combination of carboxymethylation and periodate oxidation produced a homogeneous material with short nanofibrils, having widths <20 nm and lengths <200 nm. The small dimensions of the nanofibrils reduced the viscosity of the nanocellulose, thus yielding a material with good rheological properties for use as a bioink. The nanocellulose bioink was thus used for printing 3D porous structures, which is exemplified in this study. We also demonstrated that both nanocelluloses did not support bacterial growth, which is an interesting property of these novel materials. Adam Rees, Lydia C. Powell, Gary Chinga-Carrasco, David T. Gethin, Kristin Syverud, Katja E. Hill, and David W. Thomas Copyright © 2015 Adam Rees et al. All rights reserved. Hyaluronic Acid Based Hydrogels for Regenerative Medicine Applications Tue, 19 May 2015 12:45:39 +0000 Hyaluronic acid (HA) hydrogels, obtained by cross-linking HA molecules with divinyl sulfone (DVS) based on a simple, reproducible, and safe process that does not employ any organic solvents, were developed. Owing to an innovative preparation method the resulting homogeneous hydrogels do not contain any detectable residual cross-linking agent and are easier to inject through a fine needle. HA hydrogels were characterized in terms of degradation and biological properties, viscoelasticity, injectability, and network structural parameters. They exhibit a rheological behaviour typical of strong gels and show improved viscoelastic properties by increasing HA concentration and decreasing HA/DVS weight ratio. Furthermore, it was demonstrated that processes such as sterilization and extrusion through clinical needles do not imply significant alteration of viscoelastic properties. Both SANS and rheological tests indicated that the cross-links appear to compact the network, resulting in a reduction of the mesh size by increasing the cross-linker amount. In vitro degradation tests of the HA hydrogels demonstrated that these new hydrogels show a good stability against enzymatic degradation, which increases by increasing HA concentration and decreasing HA/DVS weight ratio. Finally, the hydrogels show a good biocompatibility confirmed by in vitro tests. Assunta Borzacchiello, Luisa Russo, Birgitte M. Malle, Khadija Schwach-Abdellaoui, and Luigi Ambrosio Copyright © 2015 Assunta Borzacchiello et al. All rights reserved. Preparation, Optimization, and Screening of the Effect of Processing Variables on Agar Nanospheres Loaded with Bupropion HCl by a D-Optimal Design Tue, 19 May 2015 12:39:39 +0000 Bupropion is an atypical antidepressant drug. Fluctuating in its serum levels following oral administration of immediate release dosage forms leads to occasional seizure. The aim of the present work was designing of sustained release bupropion HCl nanospheres suited for pulmonary delivery. Agar nanospheres were prepared by transferring the w/o emulsion to solid in oil (s/o) suspension. Calcium chloride was used as cross-linking agent and hydroxypropyl β-cyclodextrin (HPβCD) was used as permeability enhancer. A response surface D-optimal design was used for optimization of nanospheres. Independent factors included in the design were calcium chloride percent, speed of homogenization, agar percent, and HPβCD percent. Optimum condition was predicted to be achieved when the calcium chloride was set at 7.19%, homogenization speed at 8500 rpm, agar content at 2%, and HPβCD at 0.12%. The optimized nanoparticles showed particle size of 587 nm, zeta potential of −30.9 mV, drug loading efficiency of 38.6%, and release efficiency of 51% until 5 h. The nanospheres showed high degree of bioadhesiveness. D-optimal response surface method is a satisfactory design to optimize the fabrication of bupropion HCl loaded agar nanospheres and these nanospheres can be successively exploited to deliver bupropion in a controlled manner for a sufficiently extended period. Jaleh Varshosaz, Mohammad Reza Zaki, Mohsen Minaiyan, and Jaafar Banoozadeh Copyright © 2015 Jaleh Varshosaz et al. All rights reserved. Assessment of Atmospheric Pressure Plasma Treatment for Implant Osseointegration Tue, 19 May 2015 10:10:11 +0000 This study assessed the osseointegrative effects of atmospheric pressure plasma (APP) surface treatment for implants in a canine model. Control surfaces were untreated textured titanium (Ti) and calcium phosphate (CaP). Experimental surfaces were their 80-second air-based APP-treated counterparts. Physicochemical characterization was performed to assess topography, surface energy, and chemical composition. One implant from each control and experimental group (four in total) was placed in one radius of each of the seven male beagles for three weeks, and one implant from each group was placed in the contralateral radius for six weeks. After sacrifice, bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) were assessed. X-ray photoelectron spectroscopy showed decreased surface levels of carbon and increased Ti and oxygen, and calcium and oxygen, posttreatment for Ti and CaP surfaces, respectively. There was a significant increase in BIC for APP-treated textured Ti surfaces at six weeks but not at three weeks or for CaP surfaces. There were no significant differences for BAFO between treated and untreated surfaces for either material at either time point. This suggests that air-based APP surface treatment may improve osseointegration of textured Ti surfaces but not CaP surfaces. Studies optimizing APP parameters and applications are warranted. Natalie R. Danna, Bryan G. Beutel, Nick Tovar, Lukasz Witek, Charles Marin, Estevam A. Bonfante, Rodrigo Granato, Marcelo Suzuki, and Paulo G. Coelho Copyright © 2015 Natalie R. Danna et al. All rights reserved. Antibacterial Effects and Biocompatibility of Titania Nanotubes with Octenidine Dihydrochloride/Poly(lactic-co-glycolic acid) Tue, 19 May 2015 09:52:35 +0000 Titanium (Ti) implants with long-term antibacterial ability and good biocompatibility are highly desirable materials that can be used to prevent implant-associated infections. In this study, titania nanotubes (TNTs) were synthesized on Ti surfaces through electrochemical anodization. Octenidine dihydrochloride (OCT)/poly(lactic-co-glycolic acid) (PLGA) was infiltrated into TNTs using a simple solvent-casting technique. OCT/PLGA-TNTs demonstrated sustained drug release and maintained the characteristic hollow structures of TNTs. TNTs (200 nm in diameter) alone exhibited slight antibacterial effect and good osteogenic activity but also evidently impaired adhesion and proliferation of bone marrow mesenchymal stem cells (BMSCs). OCT/PLGA-TNTs (100 nm in diameter) supported BMSC adhesion and proliferation and showed good osteogenesis-inducing ability. OCT/PLGA-TNTs also exhibited good long-term antibacterial ability within the observation period of 7 d. The synthesized drug carrier with relatively long-term antibacterial ability and enhanced excellent biocompatibility demonstrated significant potential in bone implant applications. Zhiqiang Xu, Yingzhen Lai, Dong Wu, Wenxiu Huang, Sijia Huang, Lin Zhou, and Jiang Chen Copyright © 2015 Zhiqiang Xu et al. All rights reserved. Clinical Application of Mesenchymal Stem Cells and Novel Supportive Therapies for Oral Bone Regeneration Tue, 12 May 2015 09:02:38 +0000 Bone regeneration is often needed prior to dental implant treatment due to the lack of adequate quantity and quality of the bone after infectious diseases, trauma, tumor, or congenital conditions. In these situations, cell transplantation technologies may help to overcome the limitations of autografts, xenografts, allografts, and alloplastic materials. A database search was conducted to include human clinical trials (randomized or controlled) and case reports/series describing the clinical use of mesenchymal stem cells (MSCs) in the oral cavity for bone regeneration only specifically excluding periodontal regeneration. Additionally, novel advances in related technologies are also described. 190 records were identified. 51 articles were selected for full-text assessment, and only 28 met the inclusion criteria: 9 case series, 10 case reports, and 9 randomized controlled clinical trials. Collectively, they evaluate the use of MSCs in a total of 290 patients in 342 interventions. The current published literature is very diverse in methodology and measurement of outcomes. Moreover, the clinical significance is limited. Therefore, the use of these techniques should be further studied in more challenging clinical scenarios with well-designed and standardized RCTs, potentially in combination with new scaffolding techniques and bioactive molecules to improve the final outcomes. Miguel Padial-Molina, Francisco O’Valle, Alejandro Lanis, Francisco Mesa, David M. Dohan Ehrenfest, Hom-Lay Wang, and Pablo Galindo-Moreno Copyright © 2015 Miguel Padial-Molina et al. All rights reserved. Biomechanical Stability of Dental Implants in Augmented Maxillary Sites: Results of a Randomized Clinical Study with Four Different Biomaterials and PRF and a Biological View on Guided Bone Regeneration Sun, 12 Apr 2015 11:49:48 +0000 Introduction. Bone regenerates mainly by periosteal and endosteal humoral and cellular activity, which is given only little concern in surgical techniques and choice of bone grafts for guided bone regeneration. This study investigates on a clinical level the biomechanical stability of augmented sites in maxillary bone when a new class of moldable, self-hardening calcium-phosphate biomaterials (SHB) is used with and without the addition of Platelet Rich Fibrin (aPRF) in the Piezotome-enhanced subperiosteal tunnel-technique (PeSPTT). Material and Methods. 82 patients with horizontal atrophy of anterior maxillary crest were treated with PeSPTT and randomly assigned biphasic (60% HA/40% bTCP) or monophasic (100% bTCP) SHB without or with addition of aPRF. 109 implants were inserted into the augmented sites after 8.3 months and the insertion-torque-value (ITV) measured as clinical expression of the (bio)mechanical stability of the augmented bone and compared to ITVs of a prior study in sinus lifting. Results. Significant better results of (bio)mechanical stability almost by two-fold, expressed by higher ITVs compared to native bone, were achieved with the used biomaterials and more constant results with the addition of aPRF. Conclusion. The use of SHB alone or combined with aPRF seems to be favourable to achieve a superior (bio)mechanical stable restored alveolar bone. Troedhan Angelo, Wainwright Marcel, Kurrek Andreas, and Schlichting Izabela Copyright © 2015 Troedhan Angelo et al. All rights reserved. Osteogenic Biomaterials in Contemporary Dentistry Wed, 08 Apr 2015 06:59:28 +0000 Seong-Hun Kim, Jae-Pyung Ahn, Homayoun H. Zadeh, and Eric J. W. Liou Copyright © 2015 Seong-Hun Kim et al. All rights reserved. An Alumina Toughened Zirconia Composite for Dental Implant Application: In Vivo Animal Results Mon, 06 Apr 2015 12:03:53 +0000 Ceramic materials are widely used for biomedical applications because of their remarkable biological and mechanical properties. Composites made of alumina and zirconia are particularly interesting owing to their higher toughness with respect to the monolithic materials. On this basis, the present study is focused on the in vivo behavior of alumina toughened zirconia (ATZ) dental implants treated with a hydrothermal process. A minipig model was implemented to assess the bone healing through histology and mRNA expression at different time points (8, 14, 28, and 56 days). The novel ATZ implant was compared to a titanium clinical standard. The implants were analyzed in terms of microstructure and surface roughness before in vivo tests. The most interesting result deals with a statistically significant higher digital histology index for ATZ implants with respect to titanium standard at 56 days, which is an unprecedented finding, to the authors’ knowledge. Even if further investigations are needed before proposing the clinical use in humans, the tested material proved to be a promising candidate among the possible ceramic dental implants. Gianmario Schierano, Federico Mussano, Maria Giulia Faga, Giulio Menicucci, Carlo Manzella, Cristian Sabione, Tullio Genova, Mitzy Mauthe von Degerfeld, Bruno Peirone, Adele Cassenti, Paola Cassoni, and Stefano Carossa Copyright © 2015 Gianmario Schierano et al. All rights reserved. Regulation of Osteoblast Differentiation by Acid-Etched and/or Grit-Blasted Titanium Substrate Topography Is Enhanced by 1,25(OH)2D3 in a Sex-Dependent Manner Mon, 06 Apr 2015 08:13:39 +0000 This study assessed contributions of micron-scale topography on clinically relevant titanium (Ti) to differentiation of osteoprogenitor cells and osteoblasts; the interaction of this effect with 1α,25-dihydroxyvitamin D3 (1α,25(OH)2D3); and if the effects are sex-dependent. Male and female rat bone marrow cells (BMCs) were cultured on acid-etched (A,  μm), grit-blasted (GB,  μm), or grit-blasted/acid-etched (SLA,  μm) Ti. BMCs were sensitive to surface topography and underwent osteoblast differentiation. This was greatest on SLA; acid etching and grit blasting contributed additively. Primary osteoblasts were also sensitive to SLA, with less effect from individual structural components, demonstrated by enhanced local factor production. Sex-dependent responses of BMCs to topography varied with parameter whereas male and female osteoblasts responded similarly to surface treatment. 1α,25(OH)2D3 enhanced cell responses on all surfaces similarly. Effects were sex-dependent and male cells grown on a complex microstructured surface were much more sensitive than female cells. These results indicate that effects of the complex SLA topography are greater than acid etching or grit blasting alone on multipotent BMCs and committed osteoblasts and that individual parameters are sex-specific. The effect of 1α,25(OH)2D3 was sex dependent. The results also suggest that levels of 1α,25(OH)2D3 in the patient may be important in osseointegration. Rene Olivares-Navarrete, Sharon L. Hyzy, Barbara D. Boyan, and Zvi Schwartz Copyright © 2015 Rene Olivares-Navarrete et al. All rights reserved. Optimizing Perfusion-Decellularization Methods of Porcine Livers for Clinical-Scale Whole-Organ Bioengineering Tue, 31 Mar 2015 06:37:14 +0000 Aim. To refine the decellularization protocol of whole porcine liver, which holds great promise for liver tissue engineering. Methods. Three decellularization methods for porcine livers (1% sodium dodecyl sulfate (SDS), 1% Triton X-100 + 1% sodium dodecyl sulfate, and 1% sodium deoxycholate + 1% sodium dodecyl sulfate) were studied. The obtained liver scaffolds were processed for histology, residual cellular content analysis, and extracellular matrix (ECM) components evaluation to investigate decellularization efficiency and ECM preservation. Rat primary hepatocytes were seeded into three kinds of scaffold to detect the biocompatibility. Results. The whole liver decellularization was successfully achieved following all three kinds of treatment. SDS combined with Triton had a high efficacy of cellular removal and caused minimal disruption of essential ECM components; it was also the most biocompatible procedure for primary hepatocytes. Conclusion. We have refined a novel, standardized, time-efficient, and reproducible protocol for the decellularization of whole liver which can be further adapted to liver tissue engineering. Qiong Wu, Ji Bao, Yong-jie Zhou, Yu-jia Wang, Zheng-gui Du, Yu-jun Shi, Li Li, and Hong Bu Copyright © 2015 Qiong Wu et al. All rights reserved. Advances in Gene Delivery Systems Mon, 30 Mar 2015 06:49:34 +0000 Surendra Nimesh, Sabina Halappanavar, Nagendra K. Kaushik, and Pradeep Kumar Copyright © 2015 Surendra Nimesh et al. All rights reserved. Delivery of Nucleic Acids and Nanomaterials by Cell-Penetrating Peptides: Opportunities and Challenges Thu, 26 Mar 2015 12:27:11 +0000 Many viral and nonviral systems have been developed to aid delivery of biologically active molecules into cells. Among these, cell-penetrating peptides (CPPs) have received increasing attention in the past two decades for biomedical applications. In this review, we focus on opportunities and challenges associated with CPP delivery of nucleic acids and nanomaterials. We first describe the nature of versatile CPPs and their interactions with various types of cargoes. We then discuss in vivo and in vitro delivery of nucleic acids and nanomaterials by CPPs. Studies on the mechanisms of cellular entry and limitations in the methods used are detailed. Yue-Wern Huang, Han-Jung Lee, Larry M. Tolliver, and Robert S. Aronstam Copyright © 2015 Yue-Wern Huang et al. All rights reserved. Biotribology in Knee Arthroplasty Thu, 26 Mar 2015 12:26:06 +0000 Thomas M. Grupp, Sandra Utzschneider, and Markus A. Wimmer Copyright © 2015 Thomas M. Grupp et al. All rights reserved. Biomaterial Hypersensitivity: Is It Real? Supportive Evidence and Approach Considerations for Metal Allergic Patients following Total Knee Arthroplasty Wed, 25 Mar 2015 09:15:31 +0000 The prospect of biomaterial hypersensitivity developing in response to joint implant materials was first presented more than 30 years ago. Many studies have established probable causation between first-generation metal-on-metal hip implants and hypersensitivity reactions. In a limited patient population, implant failure may ultimately be related to metal hypersensitivity. The examination of hypersensitivity reactions in current-generation metal-on-metal knee implants is comparatively limited. The purpose of this study is to summarize all available literature regarding biomaterial hypersensitivity after total knee arthroplasty, elucidate overall trends about this topic in the current literature, and provide a foundation for clinical approach considerations when biomaterial hypersensitivity is suspected. Andrew J. Mitchelson, Craig J. Wilson, William M. Mihalko, Thomas M. Grupp, Blaine T. Manning, Douglas A. Dennis, Stuart B. Goodman, Tony H. Tzeng, Sonia Vasdev, and Khaled J. Saleh Copyright © 2015 Andrew J. Mitchelson et al. All rights reserved. Rapid Prototyping for In Vitro Knee Rig Investigations of Prosthetized Knee Biomechanics: Comparison with Cobalt-Chromium Alloy Implant Material Tue, 24 Mar 2015 06:33:49 +0000 Retropatellar complications after total knee arthroplasty (TKA) such as anterior knee pain and subluxations might be related to altered patellofemoral biomechanics, in particular to trochlear design and femorotibial joint positioning. A method was developed to test femorotibial and patellofemoral joint modifications separately with 3D-rapid prototyped components for in vitro tests, but material differences may further influence results. This pilot study aims at validating the use of prostheses made of photopolymerized rapid prototype material (RPM) by measuring the sliding friction with a ring-on-disc setup as well as knee kinematics and retropatellar pressure on a knee rig. Cobalt-chromium alloy (standard prosthesis material, SPM) prostheses served as validation standard. Friction coefficients between these materials and polytetrafluoroethylene (PTFE) were additionally tested as this latter material is commonly used to protect pressure sensors in experiments. No statistical differences were found between friction coefficients of both materials to PTFE. UHMWPE shows higher friction coefficient at low axial loads for RPM, a difference that disappears at higher load. No measurable statistical differences were found in knee kinematics and retropatellar pressure distribution. This suggests that using polymer prototypes may be a valid alternative to original components for in vitro TKA studies and future investigations on knee biomechanics. Christian Schröder, Arnd Steinbrück, Tatjana Müller, Matthias Woiczinski, Yan Chevalier, Patrick Weber, Peter E. Müller, and Volkmar Jansson Copyright © 2015 Christian Schröder et al. All rights reserved. Patients with Intolerance Reactions to Total Knee Replacement: Combined Assessment of Allergy Diagnostics, Periprosthetic Histology, and Peri-implant Cytokine Expression Pattern Thu, 19 Mar 2015 13:17:22 +0000 We performed a combined approach to identify suspected allergy to knee arthroplasty (TKR): patch test (PT), lymphocyte transformation test (LTT), histopathology (overall grading; T- and B-lymphocytes, macrophages, and neutrophils), and semiquantitative Real-time-PCR-based periprosthetic inflammatory mediator analysis (IFNγ, TNFα, IL1-β, IL-2, IL-6, IL-8, IL-10, IL17, and TGFβ). We analyzed 25 TKR patients with yet unexplained complications like pain, effusion, and reduced range of motion. They consisted of 20 patients with proven metal sensitization (11 with PT reactions; 9 with only LTT reactivity). Control specimens were from 5 complicated TKR patients without metal sensitization, 12 OA patients before arthroplasty, and 8 PT patients without arthroplasty. Lymphocytic infiltrates were seen and fibrotic (Type IV membrane) tissue response was most frequent in the metal sensitive patients, for example, in 81% of the PT positive patients. The latter also had marked periprosthetic IFNγ expression. 8/9 patients with revision surgery using Ti-coated/oxinium based implants reported symptom relief. Our findings demonstrate that combining allergy diagnostics with histopathology and periprosthetic cytokine assessment could allow us to design better diagnostic strategies. Peter Thomas, Christine von der Helm, Christoph Schopf, Farhad Mazoochian, Lars Frommelt, Hans Gollwitzer, Josef Schneider, Michael Flaig, Veit Krenn, Benjamin Thomas, and Burkhard Summer Copyright © 2015 Peter Thomas et al. All rights reserved. PMMA Third-Body Wear after Unicondylar Knee Arthroplasty Decuples the UHMWPE Wear Particle Generation In Vitro Thu, 19 Mar 2015 09:46:07 +0000 Introduction. Overlooked polymethylmethacrylate after unicondylar knee arthroplasty can be a potential problem, since this might influence the generated wear particle size and morphology. The aim of this study was the analysis of polyethylene wear in a knee wear simulator for changes in size, morphology, and particle number after the addition of third-bodies. Material and Methods. Fixed bearing unicondylar knee prostheses (UKA) were tested in a knee simulator for 5.0 million cycles. Following bone particles were added for 1.5 million cycles, followed by 1.5 million cycles with PMMA particles. A particle analysis by scanning electron microscopy of the lubricant after the cycles was performed. Size and morphology of the generated wear were characterized. Further, the number of particles per 1 million cycles was calculated for each group. Results. The particles of all groups were similar in size and shape. The number of particles in the PMMA group showed 10-fold higher values than in the bone and control group (PMMA: 12; bone: 12; control: 12). Conclusion. The addition of bone or PMMA particles in terms of a third-body wear results in no change of particle size and morphology. PMMA third-bodies generated tenfold elevated particle numbers. This could favor an early aseptic loosening. Alexander Christoph Paulus, Manja Franke, Michael Kraxenberger, Christian Schröder, Volkmar Jansson, and Sandra Utzschneider Copyright © 2015 Alexander Christoph Paulus et al. All rights reserved. Variability of TKR Knee Kinematics and Relationship with Gait Kinetics: Implications for Total Knee Wear Thu, 19 Mar 2015 08:28:18 +0000 Several factors, including compressive load and knee kinematics, have been shown to influence wear. External knee moments (a surrogate for load) have recently been correlated with the medial and lateral wear scar areas of an unconstrained, PCL retaining knee design. Therefore, the purpose of this study was to determine whether differences in kinetics during level walking are accompanied by specific differences in relative knee kinematics. Thirty TKR patients were gait tested using the point cluster technique to obtain 3D motions of the knee. External knee moments were calculated from ground reaction forces recorded with a multicomponent force plate. The subjects were separated into two distinct anteroposterior (AP) motion categories: a low motion group and a high motion group. Similarly, the low and high motion groups for internal-external (IE) rotation were also identified. For the IE motion, there was no significant difference between the transverse internal rotation moments between the two IE motion groups. However for the AP motion groups, a higher external peak flexion moment was found for the group displaying less AP motion. These observations suggest that subjects with higher joint moments execute smaller ranges of AP motion and thus are likely to incur less wear. Valentina Ngai and Markus A. Wimmer Copyright © 2015 Valentina Ngai and Markus A. Wimmer. All rights reserved. Localized and Sustained Delivery of Erythropoietin from PLGA Microspheres Promotes Functional Recovery and Nerve Regeneration in Peripheral Nerve Injury Tue, 03 Mar 2015 09:16:11 +0000 Erythropoietin (EPO) has been demonstrated to exert neuroprotective effects on peripheral nerve injury recovery. Though daily intraperitoneal injection of EPO during a long period of time was effective, it was a tedious procedure. In addition, only limited amount of EPO could reach the injury sites by general administration, and free EPO is easily degraded in vivo. In this study, we encapsulated EPO in poly(lactide-co-glycolide) (PLGA) microspheres. Both in vitro and in vivo release assays showed that the EPO-PLGA microspheres allowed sustained release of EPO within a period of two weeks. After administration of such EPO-PLGA microspheres, the peripheral nerve injured rats had significantly better recovery compared with those which received daily intraperitoneal injection of EPO, empty PLGA microspheres, or saline treatments. This was supported by the functional, electrophysiological, and histological evaluations of the recovery done at week 8 postoperatively. We conclude that sustained delivery of EPO could be achieved by using EPO-PLGA microspheres, and such delivery method could further enhance the recovery function of EPO in nerve injury recovery. Wei Zhang, Yuan Gao, Yan Zhou, Jianheng Liu, Licheng Zhang, Anhua Long, Lihai Zhang, and Peifu Tang Copyright © 2015 Wei Zhang et al. All rights reserved. Characterization of Bone Marrow Mononuclear Cells on Biomaterials for Bone Tissue Engineering In Vitro Mon, 23 Feb 2015 10:05:13 +0000 Bone marrow mononuclear cells (BMCs) are suitable for bone tissue engineering. Comparative data regarding the needs of BMC for the adhesion on biomaterials and biocompatibility to various biomaterials are lacking to a large extent. Therefore, we evaluated whether a surface coating would enhance BMC adhesion and analyze the biocompatibility of three different kinds of biomaterials. BMCs were purified from human bone marrow aspirate samples. Beta tricalcium phosphate (β-TCP, without coating or coated with fibronectin or human plasma), demineralized bone matrix (DBM), and bovine cancellous bone (BS) were assessed. Seeding efficacy on β-TCP was 95% regardless of the surface coating. BMC demonstrated a significantly increased initial adhesion on DBM and β-TCP compared to BS. On day 14, metabolic activity was significantly increased in BMC seeded on DBM in comparison to BMC seeded on BS. Likewise increased VEGF-synthesis was observed on day 2 in BMC seeded on DBM when compared to BMC seeded on BS. The seeding efficacy of BMC on uncoated biomaterials is generally high although there are differences between these biomaterials. Beta-TCP and DBM were similar and both superior to BS, suggesting either as suitable materials for spatial restriction of BMC used for regenerative medicine purposes in vivo. Dirk Henrich, René Verboket, Alexander Schaible, Kerstin Kontradowitz, Elsie Oppermann, Jan C. Brune, Christoph Nau, Simon Meier, Halvard Bonig, Ingo Marzi, and Caroline Seebach Copyright © 2015 Dirk Henrich et al. All rights reserved. Cellular Responses Evoked by Different Surface Characteristics of Intraosseous Titanium Implants Thu, 12 Feb 2015 12:24:36 +0000 The properties of biomaterials, including their surface microstructural topography and their surface chemistry or surface energy/wettability, affect cellular responses such as cell adhesion, proliferation, and migration. The nanotopography of moderately rough implant surfaces enhances the production of biological mediators in the peri-implant microenvironment with consequent recruitment of differentiating osteogenic cells to the implant surface and stimulates osteogenic maturation. Implant surfaces with moderately rough topography and with high surface energy promote osteogenesis, increase the ratio of bone-to-implant contact, and increase the bonding strength of the bone to the implant at the interface. Certain features of implant surface chemistry are also important in enhancing peri-implant bone wound healing. It is the purpose of this paper to review some of the more important features of titanium implant surfaces which have an impact on osseointegration. Liviu Feller, Yusuf Jadwat, Razia A. G. Khammissa, Robin Meyerov, Israel Schechter, and Johan Lemmer Copyright © 2015 Liviu Feller et al. All rights reserved. Gene Profiling of Bone around Orthodontic Mini-Implants by RNA-Sequencing Analysis Wed, 11 Feb 2015 12:21:21 +0000 This study aimed to evaluate the genes that were expressed in the healing bones around SLA-treated titanium orthodontic mini-implants in a beagle at early (1-week) and late (4-week) stages with RNA-sequencing (RNA-Seq). Samples from sites of surgical defects were used as controls. Total RNA was extracted from the tissue around the implants, and an RNA-Seq analysis was performed with Illumina TruSeq. In the 1-week group, genes in the gene ontology (GO) categories of cell growth and the extracellular matrix (ECM) were upregulated, while genes in the categories of the oxidation-reduction process, intermediate filaments, and structural molecule activity were downregulated. In the 4-week group, the genes upregulated included ECM binding, stem cell fate specification, and intramembranous ossification, while genes in the oxidation-reduction process category were downregulated. GO analysis revealed an upregulation of genes that were related to significant mechanisms, including those with roles in cell proliferation, the ECM, growth factors, and osteogenic-related pathways, which are associated with bone formation. From these results, implant-induced bone formation progressed considerably during the times examined in this study. The upregulation or downregulation of selected genes was confirmed with real-time reverse transcription polymerase chain reaction. The RNA-Seq strategy was useful for defining the biological responses to orthodontic mini-implants and identifying the specific genetic networks for targeted evaluations of successful peri-implant bone remodeling. Kyung-Yen Nahm, Jung Sun Heo, Jae-Hyung Lee, Dong-Yeol Lee, Kyu-Rhim Chung, Hyo-Won Ahn, and Seong-Hun Kim Copyright © 2015 Kyung-Yen Nahm et al. All rights reserved. Resistance to Fracture of Dental Roots Obturated with Different Materials Sun, 08 Feb 2015 08:54:44 +0000 The aim of this study was to compare the vertical fracture resistance of roots obturated with different root canal filling materials and sealers. Crowns of 55 extracted mandibular premolar teeth were removed to provide root lengths of 13 mm. Five roots were saved as negative control group (canals unprepared and unfilled). Fifty root canals were instrumented and then five roots were saved as positive control group (canals prepared but unfilled). The remaining 45 roots were randomly divided into three experimental groups ( root/group) and obturated with the following procedures: in group 1, glass ionomer-based sealer and cone (ActiV GP obturation system); in group 2, bioceramic sealer and cone (EndoSequence BC obturation system); and in group 3, roots were filled with bioceramic sealer and cone (Smartpaste bio obturation system). All specimens were tested in a universal testing machine for measuring fracture resistance. For each root, the force at the time of fracture was recorded in Newtons. The statistical analysis was performed by using Kruskal-Wallis and post hoc test. There were no significant differences between the three experimental groups. The fracture values of three experimental and negative control groups were significantly higher than the positive control group. Within the limitations of this study, all materials increased the fracture resistance of instrumented roots. Berkan Celikten, Ceren Feriha Uzuntas, and Kamran Gulsahi Copyright © 2015 Berkan Celikten et al. All rights reserved. The Osteogenic Properties of Multipotent Mesenchymal Stromal Cells in Cultures on TiO2 Sol-Gel-Derived Biomaterial Sun, 01 Feb 2015 13:22:16 +0000 The biocompatibility of the bone implants is a crucial factor determining the successful tissue regeneration. The aim of this work was to compare cellular behavior and osteogenic properties of rat adipose-derived multipotent stromal cells (ASCs) and bone marrow multipotent stromal cells (BMSCs) cultured on metallic substrate covered with TiO2 sol-gel-derived nanolayer. The morphology, proliferation rate, and osteogenic differentiation potential of both ASCs and BMSCs propagated on the biomaterials were examined. The potential for osteogenic differentiation of ASCs and BMSCs was determined based on the presence of specific markers of osteogenesis, that is, alkaline phosphatase (ALP), osteopontin (OPN), and osteocalcin (OCL). Additionally, the concentration of calcium and phosphorus in extracellular matrix was determined using energy-dispersive X-ray spectroscopy (SEM-EDX). Obtained results showed that TiO2 layer influenced proliferation activity of ASCs, which manifested by shortening of population doubling time and increase of OPN secretion. However, characteristic features of cells morphology and growth pattern of cultures prompted us to conclude that ultrathin TiO2 layer might also enhance osteodifferentiation of BMSCs. Therefore in our opinion, both populations of MSCs should be used for biological evaluation of biomaterials compatibility, such results may enhance the area of investigations related to regenerative medicine. Krzysztof Marycz, Agnieszka Śmieszek, Jakub Grzesiak, Anna Siudzińska, Monika Marędziak, Anna Donesz-Sikorska, and Justyna Krzak Copyright © 2015 Krzysztof Marycz et al. All rights reserved. The Biocompatibility of Degradable Magnesium Interference Screws: An Experimental Study with Sheep Sat, 31 Jan 2015 10:06:19 +0000 Screws for ligament reconstruction are nowadays mostly made of poly-L-lactide (PLLA). However, magnesium-based biomaterials are gathering increased interest in this research field because of their good mechanical property and osteoanabolic influence on bone metabolism. The aim of this pilot study was to evaluate the biocompatibility of an interference screw for ligament reconstruction made of magnesium alloy W4 by diecasting and milling and using different PEO-coatings with calcium phosphates. PLLA and titanium screws were used as control samples. The screws were implanted in the femur condyle of the hind leg of a merino sheep. The observation period was six and twelve weeks and one year. Histomorphometric, immunohistochemical, immunofluorescence, and molecular biological evaluation were conducted. Further TEM analysis was done. In all magnesium screws a clinically relevant gas formation in the vicinity of the biomaterial was observed. Except for the PLLA and titanium control samples, no screw was fully integrated in the surrounding bone tissue. Regarding the fabrication process, milling seems to produce less gas liberation and has a better influence on bone metabolism than diecasting. Coating by PEO with calcium phosphates could not reduce the initial gas liberation but rather reduced the bone metabolism in the vicinity of the biomaterial. Ulrich Thormann, Volker Alt, Lydia Heimann, Cyrille Gasquere, Christian Heiss, Gabor Szalay, Jörg Franke, Reinhard Schnettler, and Katrin Susanne Lips Copyright © 2015 Ulrich Thormann et al. All rights reserved. Application of AMOR in Craniofacial Rabbit Bone Bioengineering Thu, 29 Jan 2015 12:15:47 +0000 Endogenous molecular and cellular mediators modulate tissue repair and regeneration. We have recently described antibody mediated osseous regeneration (AMOR) as a novel strategy for bioengineering bone in rat calvarial defect. This entails application of anti-BMP-2 antibodies capable of in vivo capturing of endogenous osteogenic BMPs (BMP-2, BMP-4, and BMP-7). The present study sought to investigate the feasibility of AMOR in other animal models. To that end, we examined the efficacy of a panel of anti-BMP-2 monoclonal antibodies (mAbs) and a polyclonal Ab immobilized on absorbable collagen sponge (ACS) to mediate bone regeneration within rabbit calvarial critical size defects. After 6 weeks, de novo bone formation was demonstrated by micro-CT imaging, histology, and histomorphometric analysis. Only certain anti-BMP-2 mAb clones mediated significant in vivo bone regeneration, suggesting that the epitopes with which anti-BMP-2 mAbs react are critical to AMOR. Increased localization of BMP-2 protein and expression of osteocalcin were observed within defects, suggesting accumulation of endogenous BMP-2 and/or increased de novo expression of BMP-2 protein within sites undergoing bone repair by AMOR. Considering the ultimate objective of translation of this therapeutic strategy in humans, preclinical studies will be necessary to demonstrate the feasibility of AMOR in progressively larger animal models. Marcelo Freire, Jeong-Ho Choi, Anthony Nguyen, Young Deok Chee, Joong-Ki Kook, Hyung-Keun You, and Homayoun H. Zadeh Copyright © 2015 Marcelo Freire et al. All rights reserved. Insight into Bone-Derived Biological Apatite: Ultrastructure and Effect of Thermal Treatment Wed, 28 Jan 2015 14:07:01 +0000 Objectives. This study aims at examining the ultrastructure of bone-derived biological apatite (BAp) from a series of small vertebrates and the effect of thermal treatment on its physiochemical properties. Materials and Methods. Femurs/fin rays and vertebral bodies of 5 kinds of small vertebrates were firstly analyzed with X-ray microtomography. Subsequently, BAp was obtained with thermal treatment and low power plasma ashing, respectively. The properties of BAp, including morphology, functional groups, and crystal characteristics were then analyzed. Results. The bones of grouper and hairtail were mainly composed of condensed bone. Spongy bone showed different distribution in the bones from frog, rat, and pigeon. No significant difference was found in bone mineral density of condensed bone and trabecular thickness of spongy bone. Only platelet-like crystals were observed for BAp obtained by plasma ashing, while rod-like and irregular crystals were both harvested from the bones treated by sintering. A much higher degree of crystallinity and larger crystal size but a lower content of carbonate were detected in the latter. Conclusion. Platelet-like BAp is the common inorganic component of vertebrate bones. BAp distributing in condensed and spongy bone may exhibit differing thermal reactivity. Thermal treatment may alter BAp’s in vivo structure and composition. Quan Liu, Haobo Pan, Zhuofan Chen, and Jukka Pekka Matinlinna Copyright © 2015 Quan Liu et al. All rights reserved. Prediction of Local Ultimate Strain and Toughness of Trabecular Bone Tissue by Raman Material Composition Analysis Wed, 28 Jan 2015 09:48:59 +0000 Clinical studies indicate that bone mineral density correlates with fracture risk at the population level but does not correlate with individual fracture risk well. Current research aims to better understand the failure mechanism of bone and to identify key determinants of bone quality, thus improving fracture risk prediction. To get a better understanding of bone strength, it is important to analyze tissue-level properties not influenced by macro- or microarchitectural factors. The aim of this pilot study was to identify whether and to what extent material properties are correlated with mechanical properties at the tissue level. The influence of macro- or microarchitectural factors was excluded by testing individual trabeculae. Previously reported data of mechanical parameters measured in single trabeculae under tension and bending and its compositional properties measured by Raman spectroscopy was evaluated. Linear and multivariate regressions show that bone matrix quality but not quantity was significantly and independently correlated with the tissue-level ultimate strain and postyield work . Principal component analysis extracted three independent components explaining 86% of the total variance, representing elastic, yield, and ultimate components according to the included mechanical parameters. Some matrix parameters were both included in the ultimate component, indicating that the variation in ultimate strain and postyield work could be largely explained by Raman-derived compositional parameters. Roberto Carretta, Edgar Stüssi, Ralph Müller, and Silvio Lorenzetti Copyright © 2015 Roberto Carretta et al. All rights reserved. Dragging Human Mesenchymal Stem Cells with the Aid of Supramolecular Assemblies of Single-Walled Carbon Nanotubes, Molecular Magnets, and Peptides in a Magnetic Field Mon, 26 Jan 2015 11:03:16 +0000 Human adipose-derived stem cells (hASCs) are an attractive cell source for therapeutic applicability in diverse fields for the repair and regeneration of damaged or malfunctioning tissues and organs. There is a growing number of cell therapies using stem cells due to their characteristics of modulation of immune system and reduction of acute rejection. So a challenge in stem cells therapy is the delivery of cells to the organ of interest, a specific site. The aim of this paper was to investigate the effects of a supramolecular assembly composed of single-walled carbon nanotubes (SWCNT), molecular magnets (lawsone-Co-phenanthroline), and a synthetic peptide (FWYANHYWFHNAFWYANHYWFHNA) in the hASCs cultures. The hASCs were isolated, characterized, expanded, and cultured with the SWCNT supramolecular assembly (SWCNT-MA). The assembly developed did not impair the cell characteristics, viability, or proliferation. During growth, the cells were strongly attached to the assembly and they could be dragged by an applied magnetic field of less than 0.3 T. These assemblies were narrower than their related allotropic forms, that is, multiwalled carbon nanotubes, and they could therefore be used to guide cells through thin blood capillaries within the human body. This strategy seems to be useful as noninvasive and nontoxic stem cells delivery/guidance and tracking during cell therapy. Ana Cláudia C. de Paula, Gustavo A. M. Sáfar, Alfredo M. Góes, Marcelo P. Bemquerer, Marcos A. Ribeiro, and Humberto O. Stumpf Copyright © 2015 Ana Cláudia C. de Paula et al. All rights reserved. Bone Regeneration of Hydroxyapatite/Alumina Bilayered Scaffold with 3 mm Passage-Like Medullary Canal in Canine Tibia Model Mon, 26 Jan 2015 06:40:44 +0000 The aim of this study was to evaluate the bone regeneration of hydroxyapatite (HA)/alumina bilayered scaffold with a 3 mm passage-like medullary canal in a beagle tibia model. A porous HA/alumina scaffold was fabricated using a polymeric template-coating technique. HA/alumina scaffold dimensions were 10 mm in outer diameter, 20 mm in length, and with either a 3 mm passage or no passage. A 20 mm segmental defect was induced using an oscillating saw through the diaphysis of the beagle tibia. The defects of six beagles were filled with HA/alumina bilayered scaffolds with a 3 mm passage or without. The segmental defect was fixated using one bone plate and six screws. Bone regeneration within the HA/alumina scaffolds was observed at eight weeks after implantation. The evaluation of bone regeneration within the scaffolds after implantation in a beagle tibia was performed using radiography, computerized tomography (CT), micro-CT, and fluorescence microscopy. New bone successfully formed in the tibia defects treated with 3 mm passage HA/alumina scaffolds compared to without-passage HA/alumina scaffolds. It was concluded that the HA/alumina bilayered scaffold with 3 mm passage-like medullary canal was instrumental in inducing host-scaffold engraftment of the defect as well as distributing the newly formed bone throughout the scaffold at 8 weeks after implantation. Jong Min Kim, Jun Sik Son, Seong Soo Kang, Gonhyung Kim, and Seok Hwa Choi Copyright © 2015 Jong Min Kim et al. All rights reserved. Nanoscale Bonding between Human Bone and Titanium Surfaces: Osseohybridization Thu, 15 Jan 2015 10:14:28 +0000 Until now, the chemical bonding between titanium and bone has been examined only through a few mechanical detachment tests. Therefore, in this study, a sandblasted and acid-etched titanium mini-implant was removed from a human patient after 2 months of placement in order to identify the chemical integration mechanism for nanoscale osseointegration of titanium implants. To prepare a transmission electron microscopy (TEM) specimen, the natural state was preserved as much as possible by cryofixation and scanning electron microscope/focused ion beam (SEM-FIB) milling without any chemical treatment. High-resolution TEM (HRTEM), energy dispersive X-ray spectroscopy (EDS), and scanning TEM (STEM)/electron energy loss spectroscopic analysis (EELS) were used to investigate the chemical composition and structure at the interface between the titanium and bone tissue. HRTEM and EDS data showed evidence of crystalline hydroxyapatite and intermixing of bone with the oxide layer of the implant. The STEM/EELS experiment provided particularly interesting results: carbon existed in polysaccharides, calcium and phosphorus existed as tricalcium phosphate (TCP), and titanium existed as oxidized titanium. In addition, the oxygen energy loss near edge structures (ELNESs) showed a possibility of the presence of CaTiO3. These STEM/EELS results can be explained by structures either with or without a chemical reaction layer. The possible existence of the osseohybridization area and the form of the carbon suggest that reconsideration of the standard definition of osseointegration is necessary. Jun-Sik Kim, Seok-Man Kang, Kyung-Won Seo, Kyung-Yen Nahm, Kyu-Rhim Chung, Seong-Hun Kim, and Jae-Pyeong Ahn Copyright © 2015 Jun-Sik Kim et al. All rights reserved. Increase in the Tibial Slope Reduces Wear after Medial Unicompartmental Fixed-Bearing Arthroplasty of the Knee Thu, 15 Jan 2015 08:07:42 +0000 Introduction. Unicompartmental arthroplasty of the knee in patients with isolated medial osteoarthritis gives good results, but survival is inferior to that of total knee prosthesis. Knees may fail because positioning of the prosthesis has been suboptimal. The aim of this study was to investigate the influence of the tibial slope on the rate of wear of a medial fixed-bearing unicompartmental knee arthroplasty. Materials and Methods. We simulated wear on a medial fixed-bearing unicompartmental knee prosthesis (Univation) in vitro with a customised, four-station, and servohydraulic knee wear simulator, which exactly reproduced the walking cycle (International Organisation for Standardisation (ISO) 14243-1:2002(E)). The medial prostheses were inserted with 3 different posterior tibial slopes: 0°, 4°, and 8° (n = 3 in each group). Results. The wear rate decreased significantly between 0° and 4° slope from 10.4 (SD 0.62) mg/million cycles to 3.22 (SD 1.71) mg/million cycles. Increasing the tibial slope to 8° did not significantly change the wear rate. Discussion. As an increase in the tibial slope reduced the wear rate in a fixed-bearing prosthesis, a higher tibial slope should be recommended. However, other factors that are influenced by the tibial slope (e.g., the tension of the ligament) must also be considered. Patrick Weber, Christian Schröder, Jens Schwiesau, Sandra Utzschneider, Arnd Steinbrück, Matthias F. Pietschmann, Volkmar Jansson, and Peter E. Müller Copyright © 2015 Patrick Weber et al. All rights reserved. Acute and Chronic Local Inflammatory Reaction after Implantation of Different Extracellular Porcine Dermis Collagen Matrices in Rats Wed, 14 Jan 2015 13:54:32 +0000 Two cross-linked acellular porcine dermal collagen matrices (Permacol and NRX) were implanted into rats and the acute and chronic local inflammatory tissue reactions were investigated after 7, 14, 28, and 112 days. Both membranes were stable in vivo for up to 112 days. All investigated immune cell populations (CD68+ macrophages, CD163+ macrophages, T lymphocytes, MHC class II positive cells, mast cells, and NK cells) were present. Their amount decreased significantly over time compared to day 7 after implantation. A change from an acute to a chronic inflammation and an associated shift from proinflammatory M1-like to anti-inflammatory M2-like macrophages were observed. In the early phase there was a significant correlation of T cells to CD68+ (M1-like) macrophages, whereas in the chronic phase T lymphocytes were positively correlated with CD163+ (M2-like) macrophages. The material NRX showed an enhanced inflammatory reaction in comparison to Permacol possibly caused by material characteristics such as a twofold higher thickness of the membrane, roughness, and water absorption capacity. Nevertheless, a more pronounced regenerative process as, for example, indicated by nestin expression demonstrated its possible suitability for applications as wound repair material. Silke Lucke, Andreas Hoene, Uwe Walschus, Anette Kob, Jens-Wolfgang Pissarek, and Michael Schlosser Copyright © 2015 Silke Lucke et al. All rights reserved. CR TKA UHMWPE Wear Tested after Artificial Aging of the Vitamin E Treated Gliding Component by Simulating Daily Patient Activities Thu, 20 Nov 2014 10:06:53 +0000 The wear behaviour of total knee arthroplasty (TKA) is dominated by two wear mechanisms: the abrasive wear and the delamination of the gliding components, where the second is strongly linked to aging processes and stress concentration in the material. The addition of vitamin E to the bulk material is a potential way to reduce the aging processes. This study evaluates the wear behaviour and delamination susceptibility of the gliding components of a vitamin E blended, ultra-high molecular weight polyethylene (UHMWPE) cruciate retaining (CR) total knee arthroplasty. Daily activities such as level walking, ascending and descending stairs, bending of the knee, and sitting and rising from a chair were simulated with a data set received from an instrumented knee prosthesis. After 5 million test cycles no structural failure of the gliding components was observed. The wear rate was with  mg/million cycles falling within the limit of previous reports for established wear test methods. Jens Schwiesau, Bernhard Fritz, Ines Kutzner, Georg Bergmann, and Thomas M. Grupp Copyright © 2014 Jens Schwiesau et al. All rights reserved. Differences in Anatomy and Kinematics in Asian and Caucasian TKA Patients: Influence on Implant Positioning and Subsequent Loading Conditions in Mobile Bearing Knees Thu, 20 Nov 2014 09:58:28 +0000 The objective of our study was to determine the mechanical stress conditions under tibiofemoral loading with an overlay of knee kinematics in deep flexion on two different mobile bearing designs in comparison to in vivo failure modes. This study investigates the seldom but severe complication of fatigue failure of polyethylene components at mobile bearing total knee arthroplasty designs. Assuming a combination of a floor-based lifestyle and tibial malrotation as a possible reason for a higher failure rate in Asian countries we developed a simplified finite element model considering a tibiofemoral roll-back angle of 22° and the range of rotational motion of a clinically established floating platform design (e.motion FP) at a knee flexion angle of 120° in order to compare our results to failure modes found in retrieved implants. Compared to the failure mode observed in the clinical retrievals the locations of the occurring stress maxima as well as the tensile stress distribution show analogies. From our observations, we conclude that the newly introduced finite element model with an overlay of deep knee flexion (lateral roll-back) and considerable internally rotated tibia implant positioning is an appropriate analysis for knee design optimizations and a suitable method to predict clinical failure modes. Allan Maas, Tae Kyun Kim, Rolf K. Miehlke, Thomas Hagen, and Thomas M. Grupp Copyright © 2014 Allan Maas et al. All rights reserved. Influence of Orthotropy on Biomechanics of Peri-Implant Bone in Complete Mandible Model with Full Dentition Mon, 03 Nov 2014 14:01:07 +0000 Objective. The study was to investigate the impact of orthotropic material on the biomechanics of dental implant, based on a detailed mandible with high geometric and mechanical similarity. Materials and Methods. Multiple data sources were used to elaborate detailed biological structures and implant CAD models. In addition, an extended orthotropic material assignment methodology based on harmonic fields was used to handle the alveolar ridge region to generate compatible orthotropic fields. The influence of orthotropic material was compared with the commonly used isotropic model and simplified orthotropic model. Results. The simulation results showed that the values of stress and strain on the implant-bone interface almost increased in the orthotropic model compared to the isotropic case, especially for the cancellous bone. However, the local stress concentration was more obvious in the isotropic case compared to that in orthotropic case. The simple orthotropic model revealed irregular stress and strain distribution, compared to the isotropic model and the real orthotropic model. The influence of orthotropy was little on the implant, periodontal ligament, tooth enamel, and dentin. Conclusion. The orthotropic material has significant effect on stress and strain of implant-bone interface in the mandible, compared with the isotropic simulation. Real orthotropic mechanical properties of mandible should be emphasized in biomechanical studies of dental implants. Xi Ding, Sheng-Hui Liao, Xing-Hao Zhu, and Hui-Ming Wang Copyright © 2014 Xi Ding et al. All rights reserved. Elastin-Coated Biodegradable Photopolymer Scaffolds for Tissue Engineering Applications Thu, 23 Oct 2014 12:45:58 +0000 One of the main open issues in modern vascular surgery is the nonbiodegradability of implants used for stent interventions, which can lead to small caliber-related thrombosis and neointimal hyperplasia. Some new, resorbable polymeric materials have been proposed to substitute traditional stainless-steel stents, but so far they were affected by poor mechanical properties and low biocompatibility. In this respect, a new material, polypropylene fumarate (PPF), may be considered as a promising candidate to implement the development of next generation stents, due to its complete biodegradability, and excellent mechanical properties and the ease to be precisely patterned. Besides all these benefits, PPF has not been tested yet for vascular prosthesis, mainly because it proved to be almost inert, while the ability to elicit a specific biological function would be of paramount importance in such critical surgery applications. Here, we propose a biomimetic functionalization process, aimed at obtaining specific bioactivation and thus improved cell-polymer interaction. Porous PPF-based scaffolds produced by deep-UV photocuring were coated by elastin and the functionalized scaffolds were extensively characterized, revealing a stable bound between the protein and the polymer surface. Both 3T3 and HUVEC cell lines were used for in vitro tests displaying an enhancement of cells adhesion and proliferation on the functionalized scaffolds. Rossella Barenghi, Szabolcs Beke, Ilaria Romano, Paola Gavazzo, Balázs Farkas, Massimo Vassalli, Fernando Brandi, and Silvia Scaglione Copyright © 2014 Rossella Barenghi et al. All rights reserved. Surface Modifications of Dental Ceramic Implants with Different Glass Solder Matrices: In Vitro Analyses with Human Primary Osteoblasts and Epithelial Cells Sun, 14 Sep 2014 00:00:00 +0000 Ceramic materials show excellent esthetic behavior, along with an absence of hypersensitivity, making them a possible alternative implant material in dental surgery. However, their surface properties enable only limited osseointegration compared to titanium implants. Within this study, a novel surface coating technique for enhanced osseointegration was investigated biologically and mechanically. Specimens of tetragonal zirconia polycrystal (TZP) and aluminum toughened zirconia (ATZ) were modified with glass solder matrices in two configurations which mainly consisted of SiO2, Al2O3, K2O, and Na2O. The influence on human osteoblastic and epithelial cell viability was examined by means of a WST-1 assay as well as live/dead staining. A C1CP-ELISA was carried out to verify procollagen type I production. Uncoated/sandblasted ceramic specimens and sandblasted titanium surfaces were investigated as a reference. Furthermore, mechanical investigations of bilaterally coated pellets were conducted with respect to surface roughness and adhesive strength of the different coatings. These tests could demonstrate a mechanically stable implant coating with glass solder matrices. The coated ceramic specimens show enhanced osteoblastic and partly epithelial viability and matrix production compared to the titanium control. Hence, the new glass solder matrix coating could improve bone cell growth as a prerequisite for enhanced osseointegration of ceramic implants. Jana Markhoff, Enrico Mick, Aurica Mitrovic, Juliane Pasold, Katharina Wegner, and Rainer Bader Copyright © 2014 Jana Markhoff et al. All rights reserved. Can Pin-on-Disk Testing Be Used to Assess the Wear Performance of Retrieved UHMWPE Components for Total Joint Arthroplasty? Thu, 11 Sep 2014 08:19:13 +0000 The objective of this study was to assess the suitability of using multidirectional pin-on-disk (POD) testing to characterize wear behavior of retrieved ultrahigh molecular weight polyethylene (UHMWPE). The POD wear behavior of 25 UHMWPE components, retrieved after 10 years in vivo, was compared with 25 that were shelf aged for 10–15 years in their original packaging. Components were gamma sterilized (25–40 kGy) in an air or reduced oxygen (inert) package. 9 mm diameter pins were fabricated from each component and evaluated against CoCr disks using a super-CTPOD with 100 stations under physiologically relevant, multidirectional loading conditions. Bovine serum (20 g/L protein concentration) was used as lubricant. Volumetric wear rates were found to vary based on the aging environment, as well as sterilization environment. Volumetric wear rates were the lowest for the pins in the gamma inert, shelf aged cohort. These results support the utility of using modern, multidirectional POD testing with a physiologic lubricant as a novel method for evaluating wear properties of retrieved UHMWPE components. The data also supported the hypothesis that wear rates of gamma-inert liners were lower than gamma-air liners for both retrieved and shelf aging conditions. However, this difference was not statistically significant for the retrieved condition. Steven M. Kurtz, Daniel W. MacDonald, Sevi Kocagöz, Mariya Tohfafarosh, and Doruk Baykal Copyright © 2014 Steven M. Kurtz et al. All rights reserved. Effects of Soft Denture Liners on L929 Fibroblasts, HaCaT Keratinocytes, and RAW 264.7 Macrophages Thu, 11 Sep 2014 06:30:56 +0000 The effects of six soft liners (Ufi Gel P (UG), Sofreliner S (SR), Durabase Soft (D), Trusoft (T), Coe Comfort (CC), and Softone (ST)) on L929, HaCat, and RAW 264.7 cells were investigated. Eluates (24 and 48 h) from the materials were applied on the cells and the viability, type of cell death, and morphology were evaluated. Cells were also seeded on the specimens’ surfaces (direct contact) and incubated (24 or 48 h), and viability was analyzed. Controls were cells in culture medium without eluates or specimens. For cell viability, no significant differences were found among materials or between extraction periods, and the liners were noncytotoxic or slightly cytotoxic. Morphology of RAW 264.7 cells was altered by the 24 h eluates from CC and D and the 48 h eluates from SR, CC, and D. The 24 and 48 h eluates from all materials (except T) increased the percentages of L929 necrotic cells. For direct contact tests, the lowest cytotoxicity was observed for UG and SR. Although eluates did not reduce viability, morphology alterations and increase in necrosis were seen. Moreover, in the direct contact, effects on viability were more pronounced, particularly for D, T, CC and ST. Thus, the use of UG and SR might reduce the risk of adverse effects. Carolina de Andrade Lima Chaves, Carlos Alberto de Souza Costa, Carlos Eduardo Vergani, Pedro Paulo Chaves de Souza, and Ana Lucia Machado Copyright © 2014 Carolina de Andrade Lima Chaves et al. All rights reserved. On the Feasibility of Utilizing Allogeneic Bone Blocks for Atrophic Maxillary Augmentation Thu, 11 Sep 2014 00:00:00 +0000 Purpose. This systematic review was aimed at assessing the feasibility by means of survival rate, histologic analysis, and causes of failure of allogeneic block grafts for augmenting the atrophic maxilla. Material and Methods. A literature search was conducted by one reviewer in several databases. Articles were included in this systematic review if they were human clinical trials in which outcomes of allogeneic bone block grafts were studied by means of survival rate. In addition other factors were extracted in order to assess their influence upon graft failure. Results. Fifteen articles fulfilled the inclusion criteria and subsequently were analyzed in this systematic review. A total of 361 block grafts could be followed 4 to 9 months after the surgery, of which 9 (2.4%) failed within 1 month to 2 months after the surgery. Additionally, a weighed mean 4.79 mm (95% CI: 4.51–5.08) horizontal bone gain was computed from 119 grafted sites in 5 studies. Regarding implant cumulative survival rate, the weighed mean was 96.9% (95% CI: 92.8–98.7%), computed from 228 implants over a mean follow-up period of 23.9 months. Histologic analysis showed that allogeneic block grafts behave differently in the early stages of healing when compared to autogenous block grafts. Conclusion. Atrophied maxillary reconstruction with allogeneic bone block grafts represents a reliable option as shown by low block graft failure rate, minimal resorption, and high implant survival rate. Alberto Monje, Michael A. Pikos, Hsun-Liang Chan, Fernando Suarez, Jordi Gargallo-Albiol, Federico Hernández-Alfaro, Pablo Galindo-Moreno, and Hom-Lay Wang Copyright © 2014 Alberto Monje et al. All rights reserved. Wear Behavior of an Unstable Knee: Stabilization via Implant Design? Tue, 09 Sep 2014 11:23:20 +0000 Background. Wear-related failures and instabilities are frequent failure mechanisms of total knee replacements. High-conforming designs may provide additional stability for the joint. This study analyzes the effects of a ligamentous insufficiency on the stability and the wear behavior of a high-conforming knee design. Methods. Two simulator wear tests were performed on a high-conforming total knee replacement design. In the first, a ligamentous-stable knee replacement with a sacrificed anterior cruciate ligament was simulated. In the second, a ligamentous-unstable knee with additionally insufficient posterior cruciate ligament and medial collateral ligament was simulated. Wear was determined gravimetrically and wear particles were analyzed. Implant kinematics was recorded during simulation. Results. Significantly higher wear rates () were observed for the unstable knee ( mg/106 cycles) compared to the stable knee ( mg/106 cycles). A higher number of wear particles with only small differences in wear particle characteristics were observed. Under unstable knee conditions, kinematics increased significantly for translations and rotations (). This increase was mainly attributed to higher tibial posterior translation and internal rotations. Conclusion. Higher kinematics under unstable test conditions is a result of insufficient stabilization via implant design. Due to the higher kinematics, increased wear was observed in this study. Jörn Reinders, Robert Sonntag, and Jan Philippe Kretzer Copyright © 2014 Jörn Reinders et al. All rights reserved. Periodontal Responses to Augmented Corticotomy with Collagen Membrane Application during Orthodontic Buccal Tipping in Dogs Tue, 09 Sep 2014 00:00:00 +0000 This prospective randomized split-mouth study was performed to examine the effects of absorbable collagen membrane (ACM) application in augmented corticotomy using deproteinized bovine bone mineral (DBBM), during orthodontic buccal tipping movement in the dog. After buccal circumscribing corticotomy and DBBM grafting into the decorticated area, flaps were repositioned and sutured on control sides. ACM was overlaid and secured with membrane tacks, on test sides only, and the flaps were repositioned and sutured. Closed coil springs were used to apply 200 g orthodontic force in the buccolingual direction on the second and third premolars, immediately after primary flap closure. The buccal tipping angles were ° and ° on the control and test sides, respectively. A mean of % of the buccal bone wall was replaced by new bone on the control side, and on the test side % was replaced. ACM application promoted an even bone surface. In conclusion, ACM application in augmented corticotomy using DBBM might stimulate periodontal tissue reestablishment, which is useful for rapid orthodontic treatment or guided bone regeneration. In particular, ACM could control the formation of mesenchymal matrix, facilitating an even bone surface. Dong-Yeol Lee, Hyo-Won Ahn, Yeek Herr, Young-Hyuk Kwon, Seong-Hun Kim, and Eun-Cheol Kim Copyright © 2014 Dong-Yeol Lee et al. All rights reserved. Clinical Evaluation of the Regenerative Potential of EMD and NanoHA in Periodontal Infrabony Defects: A 2-Year Follow-Up Mon, 08 Sep 2014 08:47:51 +0000 Introduction. The aim of this retrospective study was to compare the clinical efficacy of four different surgical techniques in promoting periodontal regeneration in patients with infrabony defects: open flap debridement, application of enamel matrix derivatives (EMD), nanohydroxyapatite (nanoHA) application, and combined nanoHA and EMD application. Probing attachment level (PAL), pocket depth (PD), and position of gingival margin at completion of therapy (REC) were measured. Materials and Methods. Data were collected from 64 healthy patients (34 women and 30 men, mean age 37,7 years). Clinical indices were measured by a calibrated examiner at baseline and at 12, 18, and 24 months. The values obtained for each treatment were compared using nonparametric tests. Results. All treatments resulted in a tendency toward PD reduction over time, with improvements in REC and PAL. The differences in PD, REC, and PAL values at baseline compared with values after 12, 18, and 24 months were statistically significant for all treatments. Statistically significant differences in PAL and PD were detected between nanoHA and nanoHA + EMD at 12, 18, and 24 months. Conclusion. In this study, EMD and nanoHA used together in patients with infrabony periodontal lesions had better clinical efficacy than nanoHA alone, EMD alone, or open flap debridement. Andrea Pilloni, Matteo Saccucci, Gabriele Di Carlo, Blerina Zeza, Marco Ambrosca, Michele Paolantonio, Gilberto Sammartino, Claudio Mongardini, and Antonella Polimeni Copyright © 2014 Andrea Pilloni et al. All rights reserved. Serum Metal Ion Concentrations in Paediatric Patients following Total Knee Arthroplasty Using Megaprostheses Mon, 08 Sep 2014 06:38:39 +0000 The purpose of this study was to determine the concentrations of cobalt, chromium, and molybdenum in the serum of paediatric tumour patients after fixed hinge total knee arthroplasty. Further, these metal ion levels were compared with serum metal ion levels of patients with other orthopaedic devices such as hip and knee prostheses with metal-on-metal or metal-on-polyethylene articulation to find differences between anatomical locations, abrasion characteristics, and bearing surfaces. After an average follow-up of 108 months (range: 67 to 163) of 11 paediatric patients with fixed hinge total knee arthroplasty, the mean concentrations for Co and Cr were significantly increased while Mo was within the limits compared to the upper values from the reference laboratory. Furthermore, these serum concentrations were significantly higher compared to patients with a standard rotating hinge device ( and ) and preoperative controls . On the other hand, the serum levels of patients following MoM THA or rotating hinge arthroplasty using megaprostheses were higher. Therefore, periodic long-term follow-ups are recommended due to the rising concerns about systemic metal ion exposure in the literature. Upon the occurrence of adverse reactions to metal debris the revision of the fixed hinge implant should be considered. Jörg Friesenbichler, Patrick Sadoghi, Werner Maurer-Ertl, Joanna Szkandera, Mathias Glehr, Kathrin Ogris, Matthias Wolf, Christian Weger, and Andreas Leithner Copyright © 2014 Jörg Friesenbichler et al. All rights reserved. Dynamic Contact Angle Analysis of Protein Adsorption on Polysaccharide Multilayer’s Films for Biomaterial Reendothelialization Mon, 08 Sep 2014 00:00:00 +0000 Atherosclerosis is a major cardiovascular disease. One of the side effects is restenosis. The aim of this work was to study the coating of stents by dextran derivates based polyelectrolyte’s multilayer (PEM) films in order to increase endothelialization of injured arterial wall after stent implantation. Films were composed with diethylaminoethyl dextran (DEAE) as polycation and dextran sulphate (DS) as polyanion. One film was composed with 4 bilayers of (DEAE-DS)4 and was labeled D−. The other film was the same as D− but with an added terminal layer of DEAE polycation: (DEAE-DS)4-DEAE (labeled D+). The dynamic adsorption/desorption of proteins on the films were characterized by dynamic contact angle (DCA) and atomic force microscopy (AFM). Human endothelial cell (HUVEC) adhesion and proliferation were quantified and correlated to protein adsorption analyzed by DCA for fibronectin, vitronectin, and bovine serum albumin (BSA). Our results showed that the endothelial cell response was optimal for films composed of DS as external layer. Fibronectin was found to be the only protein to exhibit a reversible change in conformation after desorption test. This behavior was only observed for (DEAE-DS)4 films. (DEAE-DS)4 films could enhance HUVEC proliferation in agreement with fibronectin ability to easily change from conformation. Safiya Benni, Thierry Avramoglou, Hanna Hlawaty, and Laurence Mora Copyright © 2014 Safiya Benni et al. All rights reserved. In Vitro Bioactivity and Antimicrobial Tuning of Bioactive Glass Nanoparticles Added with Neem (Azadirachta indica) Leaf Powder Sun, 07 Sep 2014 07:45:09 +0000 Silica and phosphate based bioactive glass nanoparticles (58SiO2-33CaO-9P2O5) with doping of neem (Azadirachta indica) leaf powder and silver nanoparticles were prepared and characterised. Bioactive glass nanoparticles were produced using sol-gel technique. In vitro bioactivity of the prepared samples was investigated using simulated body fluid. X-ray diffraction (XRD) pattern of prepared glass particles reveals amorphous phase and spherical morphology with a particle size of less than 50 nm. When compared to neem doped glass, better bioactivity was attained in silver doped glass through formation of hydroxyapatite layer on the surface, which was confirmed through XRD, Fourier transform infrared (FTIR), and scanning electron microscopy (SEM) analysis. However, neem leaf powder doped bioactive glass nanoparticles show good antimicrobial activity against Staphylococcus aureus and Escherichia coli and less bioactivity compared with silver doped glass particles. In addition, the biocompatibility of the prepared nanocomposites reveals better results for neem doped and silver doped glasses at lower concentration. Therefore, neem doped bioactive glass may act as a potent antimicrobial agent for preventing microbial infection in tissue engineering applications. M. Prabhu, S. Ruby Priscilla, K. Kavitha, P. Manivasakan, V. Rajendran, and P. Kulandaivelu Copyright © 2014 M. Prabhu et al. All rights reserved.