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BioMed Research International
Volume 2016, Article ID 7374129, 12 pages
http://dx.doi.org/10.1155/2016/7374129
Review Article

Soft Tissue Augmentation Techniques in Implants Placed and Provisionalized Immediately: A Systematic Review

1Department of Stomatology, Faculty of Health Sciences, Rey Juan Carlos University (URJC), Avenida Atenas s/n, 28922 Madrid, Spain
2Department of Stomatology and Maxillofacial Surgery, Federico II University, Corso Umberto I 40, 80138 Naples, Italy
3Department of International Dentistry Research, Faculty of Medicine and Dentistry, San Antonio Catholic University of Murcia (UCAM), Avenida Jerónimos 135, 30107 Murcia, Spain

Received 15 January 2016; Revised 28 May 2016; Accepted 13 June 2016

Academic Editor: Konstantinos Michalakis

Copyright © 2016 Rosa Rojo et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

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.

1. Introduction

After tooth extraction, a number of changes take place in the socket during the following 12 months of surgery. The width of the ridge will be reduced by 50% (about 5 to 7 mm); two-thirds of this reabsorption occurs after the first three months [1]. These changes expressed both horizontally and vertically are expected in hard and soft tissues [2]. However, further bone loss occurs horizontally and increased resorption of the vestibular cortical thickness [3] results in a more palatal position after the alveolar ridge resorption process [4].

Immediate implant placement (IIP) reduces alveolar resorption [5, 6], the number of surgeries, and the waiting time necessary until the placement of the final restoration [7, 8]. Surgeons should however consider many factors to achieve success in the treatment such as the location of the implant, gingival marginal position, width and thickness of keratinized mucosa [9], gingival biotype [10], vestibular cortical thickness, and the size of the horizontal “gap” buccal or sagittal position of the root [11].

To optimally preserve tissue, surgeons implement IIP [12] to maintain bone architecture and immediate provisionalization to maintain soft tissue [13]. However, the appearance of gingival recession has been reported after the first year in the vestibular cortex [1416]. To increase thickness of the gingival tissues practitioners have suggested using connective tissue grafts (ITC) as a method of preservation of soft tissue levels [12, 17, 18].

A connective tissue graft associated with IIP was described by Edel [19] who used a biological membrane to cover the residual alveolar defects associated with tooth extraction and considered it a valid protocol [20, 21] against the use of synthetic membranes that show more clinical complications, such as colonization and bacterial infection [22, 23]. Biological membranes also improve metabolic environment of the local soft tissue surface preserving the amount of keratinized tissue and allow for optimal marginal and peri-implants seals [24]. We have therefore developed an associated surgical procedure based on IIP palatal flaps rotation to obtain and maintain coverage of primary soft tissue and crestal bone augmentation following placement of the IIP [25, 26].

Some systematic reviews report the effectiveness of soft tissue augmentation procedures around dental implants and in partially edentulous sites [27] and changes in mucosal soft tissue thickness and keratinized mucosa width after soft tissue grafting around dental implants [28] or evaluate success, the function, complications, and patient satisfaction between “immediate,” “immediate-delayed,” and “delayed” implants [29]. However, there is still a limited number of articles analysing this type of mucogingival technique in the immediate implants. The aims of this review were (1) to evaluate the effectiveness of mucogingival techniques after extraction and implant placement in adult patients in randomized controlled trials (RCT), prospective clinical trials (PCT), and case series (CS) and (2) to analyse the changes in aesthetic and clinical outcomes in the peri-implant tissues.

2. Material and Methods

The reporting of this systematic review is based on the PRISMA guidelines [30]. A structured approach was used to formulate the research question for this systematic review using five components commonly known by the acronym “PICOS” [31]: the patient population (P), the interventions (I), the comparison group (C), the outcome of interest (O), and the study design (S).

We therefore chose studies that demonstrated this:Participants: adult patients who needed a dental extraction and who required an immediate implant treatment.Interventions: use of connective tissue graft alone or combined with immediate provisionalization and use of rotated palatal graft.Comparisons: no use of mucogingival and immediate restoration techniques.Outcome: changes in aesthetic and clinical outcomes.Study design: randomized controlled trials (RCT), prospective clinical trials (PCT), or case series (CS).

2.1. Search Strategy

An electronic search was performed in PubMed, Scopus, ISI Web, and the Cochrane Oral Health Group Specialized Trials Register (RCTs) database until the 21st of May 2015. Two authors (Rosa Rojo and Jesús Rodríguez-Molinero) performed all searches and selected articles fulfilling the inclusion criteria independently and in duplicate (Figure 1). The level of agreement between the reviewers regarding study inclusion was calculated using Cohen’s kappa statistic.

Figure 1: Flow chart of the literature search.
2.2. Search Terms

The following search algorithm was used: ((dental (MeSH) OR immediate (MeSH)) AND implants (MeSH)) AND (“connective tissue graft” (free text word) OR “free gingival graft” (free text word) OR “rotated palatal flap” (free text word)) OR “immediate provisionalization” (free text word) OR “immediate implant restoration” (free text word).

2.3. Inclusion and Exclusion Criteria

The included study articles had to fulfil all the following criteria: (1) randomized and controlled clinical trials, prospective clinical trials, or case series; (2) at least ten human participants; (3) full-text no language restrictions; (4) studies that carried out immediate placement of dental implant(s); (5) use of connective tissue and/or pedicle flap techniques; (6) with or without immediate provisionalization; (7) the use of any type of graft material.

Reviews and case reports were excluded from this study.

2.4. Assessments of Study Quality

Following the selection of eligible papers on the basis of inclusion and exclusion criteria, studies were rated on their quality. Specific study design related forms were designed by the Dutch Cochrane Collaboration based on the Cochrane Handbook for Systematic Reviews of Interventions [41]. We developed a checklist for each study type, focusing on randomization (if applicable), patient and site characteristics, patient selection, intervention, evaluation method, outcome, and follow-up (Table 1).

Table 1: Checklist for quality assessment. N/A: not applicable; : items applicable to prospective controlled clinical trial.

Two investigators (Rosa Rojo and Jesús Rodríguez-Molinero) independently generated a score for all selected articles expressed as the amount of plus signs given. A score of at least 8 was considered methodologically acceptable for RCTs and that of 7 was acceptable for PCT and CS. To reduce the risk for bias as much as possible, studies showing poor quality on the basis of this assessment were excluded.

2.5. Statistical Analysis

A Cohen’s kappa statistic was used to evaluate interexaminer agreement on study eligibility and quality.

Due to the heterogeneity between the techniques used in the studies (flapless/graft), a meta-analysis on the survival rates of implants and the rate of suitable aesthetic levels was performed.

Survival rates were calculated by dividing the number of events (survival of the implants or suitable aesthetic results) in the numerator by the total exposure time obtained in the denominator, which is calculated by taking the sum of exposure time of implants that survived the total follow-up time, exposure time up to the failure of implants lost during the observation time, and exposure time up to the end of follow-up time for implants that did not complete the observation period due to any reason.

To evaluate the suitable aesthetic results only studies that had applied aesthetic indexes are included.

The total number of survival rates was considered to be Poisson distributed and Poisson’s regression with a logarithmic link function was used. Standard errors were calculated to obtain 95% confidence intervals (CIs) of the summary estimates of the survival rates.

To assess heterogeneity of the study-specific event rates, statistics was done and also the value was calculated. If , indicating heterogeneity, random-effects Poisson’s regression was used to obtain a summary estimate of the survival rates. Survival proportions were calculated by the relationship between survival rate and number of implants evaluated.

All analysis were done using R version 3.1.3 (R Core Development Team, R Foundation, Vienna, Austria) with the interrater reliability (irr) package and metafor package.

3. Results

3.1. Search Results

All search strategies yielded 738 papers. Two investigators (Jesús Rodríguez-Molinero and Rosa Rojo) independently identified 17 potentially eligible papers. Interexaminer agreement on study eligibility was high (, ). Eligible studies were methodologically assessed by the same investigators with high agreement (, ). Three studies [7, 32, 33] did not meet the inclusion criteria and were excluded. The reasons for exclusion are depicted in Table 2.

Table 2: Studies excluded after quality assessment and reasons for exclusion.

One examiner (Rosa Rojo) extracted all data from the selected papers. Finally, 14 papers could be identified. The characteristics of included studies are described in Tables 3 and 4. Nine studies were case series, two were prospective clinical trials, and three were randomized clinical trials. Clinical requirements to be met by the patient are detailed in Table 5.

Table 3: Characteristics of included studies. RCT: randomized clinical trial; PCT: prospective clinical trial; CS: case series; f: female; m: male; mo: months.
Table 4: Characteristics of the clinical procedure of included studies. N: no; Y: yes; SCTG: subepithelial connective tissue graft; IIPP: immediate implant placement and provisionalization; IIP: immediate implant placement; RPF: rotated palatal flap; TG: test group; CG: control group.
Table 5: Patient profile: inclusion and exclusion criteria.
3.2. Study Investigations

Only two of the studies used the rotated palatal flap (RPF) as a technique for increasing the soft tissue and the rest used subepithelial connective tissue graft (SCTG). One study evaluated the long-term effectiveness over a period of up to nine years and one showed clinical efficacy of implant placement for the treatment of nonsalvageable teeth that showed gingival recession or absence of attached gingiva. The parameters evaluated in the studies varied; examinations included the changes in the soft and hard tissues [17, 18, 21, 34, 3638] and in the all tissue response to the peri-implant [39, 40]. Aesthetic results [35] and rates of success [18, 21, 3740] also differed between studies.

Also, Nemcovsky et al. [25] reported the use of palatal coverage rotational flap without using membranes to regenerate the crestal bone and which surgical approach was used to allow primary closure [26].

3.3. Preoperative and Postoperative Care

Preoperative. Some studies reported various preoperative treatments, such as oral administration of an antibiotic one hour prior to surgery, for example, 2 g amoxicillin or 600 g clindamycin for patients allergic to penicillin [17] or 500 mg amoxicillin four times daily for 4 days [20].

Postoperative. Patients were instructed to rinse twice daily with chlorhexidine digluconate [17] (0.12% [12, 18, 26, 39, 40] or 0.2% [35]) and to refrain from removing plaque by mechanical means at the surgical site for 2 weeks [39, 40]. Sutures were removed 2 weeks postoperatively, and patients were asked to commence plaque removal at the provisional crown with a soft-bristled toothbrush [17].

Antibiotics and an analgesic were prescribed [18, 35, 38] such as system antibiotics (amoxicillin 625 mg + clavulanic 125 mg two times daily [36] or amoxicillin 500 mg thrice daily for 5 days [21]) and nonsteroidal anti-inflammatory medication (aceclofenac 100 mg two times daily [36] or diclofenac sodium + serratiopeptidase combination thrice daily for 3 days [21]).

A liquid diet was suggested for 1 or 2 weeks [18, 3840] following surgery with a transition to a soft diet for the next 3 months [18, 3840].

3.4. Implant Survival

In two studies, the implant survival rate was 90% [39, 40]. One implant developed a periapical infection 3 weeks after implant placement [39] and the other patient experienced an early implant failure at the 3-month follow-up appointment due to mobility [40]. The implant survival in the rest of the studies was 100%.

In meta-analysis, the annual survival rate of the implant was estimated at 6,526 (6,125–6,927) per 100 years for model of random effects ( = 93,21%) (Figure 2) translating into the survival of implant as observed in Table 6.

Table 6: Survival rate of implant and survival rate of suitable aesthetic results. Total exposure time corresponds to the sum of exposure time of implants that survived the follow-up time, exposure time to the failure of implants lost during the observation time, and exposure time up to the end of follow-up time for the implants that did not complete the observation period due to any reason.
Figure 2: Forest plot for survival rate of proportion of implants evaluated. Proportion ratio corresponds to the percentage of survival implants between the total number of implants evaluated.

The meta-analysis shown in the forest plot (Figure 2) shows survival proportion of the number of implants evaluated.

3.5. Aesthetic Outcomes

The evaluation of the aesthetic results was assessed using the stability of the keratinized mucosa width (KMW) parameters. The mean values of KMW >3 mm were considered acceptable for aesthetic purpose. All patients treated by immediate implant combined with subepithelial connective tissue graft had a KMW value >3 mm at the end of each of the studies’ follow-up periods [20, 21, 36]. Stability of this tissue during the 9-year period was reported in one publication [6].

In the experimental groups of studies, none reported aesthetic compromises and, overall, the aesthetic outcomes were quite favourable [7]. In some studies, pink aesthetic score (PES) and white aesthetic score (WES) indexes were used by two independent evaluators. The first evaluates the mesial papilla, distal papilla, curvature of the facial mucosa, level of the facial mucosa, and root convexity/soft tissue color and texture at the facial aspect of the facial implant site as five variables. The second index evaluates the visible part of the implant restoration such as general tooth form, outline and volume of the clinical crown, color, surface texture, translucency, and characterization. In both, a score of 2, 1, or 0 is assigned to each parameter. Thus, in case of an implant restoration, a maximum total PES or WES of 10 is possible. We derived a mean pink aesthetic score (PES) of 7.15 (SD: 1.75) and a mean white aesthetic score (WES) of 7.98 (SD: 0.99). A statically significant difference between control and test groups was revealed for PES scores () while no differences were revealed for WES () [17].

For aesthetic reasons, 1 mm was the maximum discrepancy accepted for attesting to a good alignment of emergence lines (ELs) of the prosthetic crown. The collected data demonstrated a complete success in the 1–3-year test group, while a mean of 80% of the control group showed scores of EL > 1 mm. A low decrement of mean EL scores > 1 mm was reported in the following 6-year interval in both groups [6].

3.6. Biological Parameters

The modified plaque index (mPI) demonstrated scores of 0 and 1. There was no statistically significant difference in the mPI at the end of the follow-up period () [39, 40].

All sites that showed a probing depth (PD) value < 3 mm were considered healthy. Covani et al. [20] results showed a mean decrease of PD value between the baseline measurements and the PD value at the end of the follow-up period [21].

After 12 months of surgery, more than 50% of the papilla fill was observed in 80% [18, 39] and 89% [40] of all sites. The papilla index score (PIS) ranged from 0 to 3 at all the time intervals in the studies of Yoshino et al. [18] and Chung et al. [40]. In other studies, the PIS ranged from 2 to 3 [37, 39]; for Lee et al. [36], the PIS ranged from 1 to 3 at all time intervals. No statistically significant differences were noted for either mesial or distal papilla levels among the time intervals and between the test and control groups ().

The intraclass correlation coefficient (ICC) for facial gingival level (FGL) measurements was 0.92 [39] and 0.998 [40], indicating that the measurement method was reliable and reproducible. The mean FGL change at the end of the follow-up period was −0.05 mm [39, 40], +0.13 ± 0.61 [37], and −0.25 ± 0.35 [18] (). No statistically significant differences for FGL were noted between any of the time intervals.

The mean of periotest values (PTV) at T3 (−2.6 ±−5.5) [39] (−2.0 ± 0.9) [40] was statistically significantly lower than that at T1 (−0.2 ± 3.8) [39] (−0.1 ± 2.2) [40] (), which indicated good stability for the implants.

3.7. Radiographic Results

There were no significant differences in marginal bone level (MBL) or in the MBL change either at or between any time intervals between the test and control groups () [18].

The intraclass correlation coefficient (ICC) for MBL measurements was 0.99 [39] and 0.955 [40], indicating that the measurement method was reliable and reproducible. The mean value of the MBL was  mm [20],  mm [17], +0.10 mm [39], and −0.31 mm [40] at the end of the follow-up period.

3.8. Complications

All studies showed generally intraoperative and postoperative complications. In the surgical phase, they reported complications of rotational instability observed in any implants [18, 39] and partial necrosis of the SCTG [39, 40]. Eventually, immediate postsurgical bleeding in the palate occurred and there were granules of the grafting material exfoliating at this position during the first healing weeks [26].

In the prosthetic phase, studies reported the following complications: episodes of provisional restoration debonding [18, 38, 40], fractures in the provisional restorations [40], abutment screw loosening [39, 40], and a fistula tract as a result of the residual flow of composite resin [18, 39].

3.9. Survival Suitable Aesthetic Results

In the meta-analysis only those studies whose indexes include applied information were available in a follow-up of 12 months.

PIS indexes of 5 studies [3537, 39, 40] were included, considering those unfavorable aesthetic results scores equal to or less than 2; PES index of Migliorati et al. [17] was included, considering those unfavorable aesthetic results scores equal to or below 5; the FGL of 2 studies [18, 38] was included, considering unfavorable aesthetic results whose measurements were greater than 1.5 mm.

The annual aesthetic suitable rate of the implant was estimated at 1,292 (1,029–1,555) per 5 years for model of random effects ( = 64,32%) translating into the survival of implant as observed in Table 6.

The meta-analysis shown in the forest plot (Figure 3) of the proportion of suitable aesthetic results of the number of implants evaluated.

Figure 3: Forest plot for proportion of suitable aesthetic results rate of implants evaluated. Proportion ratio corresponds to the percentage of suitable aesthetic results between the total number of implants evaluated.

4. Discussion

In this paper, we have presented a systematic review of studies that demonstrate techniques for implant placement after tooth extraction. We examined those studies that use autologous connective tissue graft or a rotational palatal flap as options for effective treatment that would compensate for the expected loss of volume labial soft tissue and maintain good aesthetic results over time.

The results showed that all of the studies reported positive behaviour of soft tissue and bone peri-implants. This technique could minimize facial gingival recession; accordingly, several studies observed an increase in gingival tissue of 0.07 mm [37], 0.2 mm [35], 0.25 mm [39], 0.4 mm [36], or 0.5 mm [38]. The use of connective tissue grafts seems to prevent induced complications by using synthetic membranes, improving metabolism in the local environment of superficial tissues [21], and by increasing the height and thickness of the tissue [21, 36, 38], especially if the implants are positioned palatally [20, 34, 38, 39]. This is especially useful in cases of insufficient soft tissue and transformation of a thin gingival biotype to a thick one [37], allowing a sufficient thickness of peri-implant to hide various underlying restoration materials (titanium, titanium-ceramic, zirconia ceramic, and zirconia) [34].

Performing the technique with a rotational palatal flap showed predictable results with or without the use of membranes and was advantageous because it retains some of the blood supply [25]. However, this procedure is not advisable when the probing of the palatal gingiva measured <4 mm [26].

Several factors associated with bone resorption have been reported as due to flap elevation; although some studies [17, 42] argue that lack of flap elevation does not prevent reabsorption, it is vitally important to choose a suitable profile of the patient. The thickness of the bones can also determine the degree to which vertical resorption is produced [38, 40, 43]. Sites with thinner facial bone underwent significantly more vertical resorption than sites with thicker facial bone. The major benefit of this treatment is the preservation of the existing papillae with no risk of creating scar tissue.

The studies reported good results in the absence of using provisional restorations [37]. However, in the study of Yoshino et al. [18], the experimental group receiving the subepithelial connective tissue graft and provisionalization experienced fewer changes in facial gingival levels compared to those not receiving the connective tissue graft.

Although the influence of oral hygiene on implant success has been controversial, it is generally agreed on that plaque accumulation could induce a negative response in the mucosa without a good level of oral hygiene [37, 40]. To minimize disruption to the peri-implant gingival tissue and ISTC teeth immediately after replacement, patients were advised to thoroughly rinse with chlorhexidine solution but refrain from brushing the surgical site for one month following the procedure [39].

In this systematic review, eligible studies were rated on their quality using specific study design related forms designed by the Dutch Cochrane Collaboration. This method was also used by Den Hartog et al. [44] to evaluate the outcome of immediate, early, and conventional single implant treatment. Note that other checklists based on the CONSORT statement for RCTs [45] or STROBE statement for case series [46] could also have been used to evaluate methodological background. Albeit one search method may be considered more detailed than another, we believe that the two papers we excluded would have been omitted in any quality assessment as clear data on the outcome were missing.

Randomized clinical trial, prospective clinical trials, and case series studies were included in this meta-analysis to summarize data on survival rates and the failure of the implants with these techniques.

After the period of investigation, the highest rates of failure (10%) were observed in studies of Tsuda et al. [39] and Chung et al. [40]. However, the sample size was insufficient (10 implants per study) and due to heterogeneity between variables (flap technique, graft, provisionalization, and using membrane) it was not possible to determine whether any of them could affect the survival of the implant.

For the meta-analytic study of soft tissues higher rates of failure (70%) were observed in the study of Tsuda et al. [39], where the implant failure is also accompanied, which could be due to an inadequate assessment of the clinical variables intervention protocol, since due to heterogeneity between variables it was not possible to determine if any of them could have significantly affected the results.

Studies Kan et al. [38] and Cornelini et al. [35] are the only ones that combine the technique with flap and flapless, with unfavorable cosmetic results (68% and 65%, resp.). However, studies of Yoshino et al. [18] and Lee et al. [36] (with failure rates of 0% and 30%, resp.) do not employ flap, but the study of Kan et al. [37] (with aesthetic failure rate of 16%) is used. In all grafts, they are used. These results suggest that the use of the flap does not seem to influence the final results.

Immediately placing the implant is especially the most advanced treatment modality, reducing the number of surgical treatments and the time between tooth extraction and positioning of the definitive prosthesis. The option presented by this systematic review is an effective means to compensate for the expected loss of lip volume of soft tissue that maintains good aesthetic results over time. It is a simple, safe, and reliable method to achieve functional and aesthetic restorations with a high degree of success [6, 17, 20, 34, 35].

However, stabilization of tissues is documented in the last period of 6–9 years, so most retrospective studies would be desirable to support the predictability of positive change at the level of the soft and hard tissues.

Competing Interests

The authors declare that they have no competing interests.

Authors’ Contributions

Rosa Rojo and Juan Carlos Prados-Frutos equally contributed to this paper.

References

  1. L. Schropp, A. Wenzel, L. Kostopoulos, and T. Karring, “Bone healing and soft tissue contour changes following single-tooth extraction: a clinical and radiographic 12-month prospective study,” The International Journal of Periodontics and Restorative Dentistry, vol. 23, no. 4, pp. 313–323, 2003. View at Google Scholar · View at Scopus
  2. F. van der Weijden, F. Dell'Acqua, and D. E. Slot, “Alveolar bone dimensional changes of post-extraction sockets in humans: a systematic review,” Journal of Clinical Periodontology, vol. 36, no. 12, pp. 1048–1058, 2009. View at Publisher · View at Google Scholar · View at Scopus
  3. W. L. Tan, T. L. T. Wong, M. C. M. Wong, and N. P. Lang, “A systematic review of post-extractional alveolar hard and soft tissue dimensional changes in humans,” Clinical Oral Implants Research, vol. 23, no. 5, pp. 1–21, 2012. View at Publisher · View at Google Scholar · View at Scopus
  4. D. Botticelli, T. Berglundh, and J. Lindhe, “Hard-tissue alterations following immediate implant placement in extraction sites,” Journal of Clinical Periodontology, vol. 31, no. 10, pp. 820–828, 2004. View at Publisher · View at Google Scholar · View at Scopus
  5. S. L. Wheeler, R. E. Vogel, and R. Casellini, “Tissue preservation and maintenance of optimum esthetics: a clinical report,” The International Journal of Oral & Maxillofacial Implants, vol. 15, no. 2, pp. 265–271, 2000. View at Google Scholar · View at Scopus
  6. A. E. Bianchi and F. Sanfilippo, “Single-tooth replacement by immediate implant and connective tissue graft: a 1–9-year clinical evaluation,” Clinical Oral Implants Research, vol. 15, no. 3, pp. 269–277, 2004. View at Publisher · View at Google Scholar · View at Scopus
  7. U. Grunder, G. Polizzi, R. Goené et al., “A 3-year prospective multicenter follow-up report on the immediate and delayed-immediate placement of implants,” The International Journal of Oral & Maxillofacial Implants, vol. 14, no. 2, pp. 210–216, 1999. View at Google Scholar · View at Scopus
  8. L. Vanden Bogaerde, B. Rangert, and I. Wendelhag, “Immediate/early function of Brånemark System® TiUnite implants in fresh extraction sockets in maxillae and posterior mandibles: An 18-month Prospective Clinical Study,” Clinical Implant Dentistry and Related Research, vol. 7, no. 1, pp. S121–S130, 2005. View at Publisher · View at Google Scholar · View at Scopus
  9. G.-H. Lin, H.-L. Chan, and H.-L. Wang, “The significance of keratinized mucosa on implant health: a systematic review,” Journal of Periodontology, vol. 84, no. 12, pp. 1755–1767, 2013. View at Publisher · View at Google Scholar · View at Scopus
  10. J.-H. Fu, C.-Y. Yeh, H.-L. Chan, N. Tatarakis, D. J. M. Leong, and H.-L. Wang, “Tissue biotype and its relation to the underlying bone morphology,” Journal of Periodontology, vol. 81, no. 4, pp. 569–574, 2010. View at Publisher · View at Google Scholar · View at Scopus
  11. G.-H. Lin, H.-L. Chan, and H.-L. Wang, “Effects of currently available surgical and restorative interventions on reducing midfacial mucosal recession of immediately placed single-tooth implants: a systematic review,” Journal of Periodontology, vol. 85, no. 1, pp. 92–102, 2014. View at Publisher · View at Google Scholar · View at Scopus
  12. J. Y. K. Kan, K. Rungcharassaeng, and J. L. Lozada, “Bilaminar subepithelial connective tissue grafts for immediate implant placement and provisionalization in the esthetic zone,” Journal of the California Dental Association, vol. 33, no. 11, pp. 865–871, 2005. View at Google Scholar · View at Scopus
  13. P. S. Wöhrle, “Single-tooth replacement in the aesthetic zone with immediate provisionalization: fourteen consecutive case reports,” Practical Periodontics & Aesthetic Dentistry, vol. 10, no. 9, pp. 1107–1116, 1998. View at Google Scholar · View at Scopus
  14. J. Y. K. Kan, K. Rungcharassaeng, and J. Lozada, “Immediate placement and provisionalization of maxillary anterior single implants: 1-Year prospective study,” The International Journal of Oral & Maxillofacial Implants, vol. 18, no. 1, pp. 31–39, 2003. View at Google Scholar · View at Scopus
  15. T. De Rouck, K. Collys, and J. Cosyn, “Immediate single-tooth implants in the anterior maxilla: a 1-year case cohort study on hard and soft tissue response,” Journal of Clinical Periodontology, vol. 35, no. 7, pp. 649–657, 2008. View at Publisher · View at Google Scholar · View at Scopus
  16. P. Palattella, F. Torsello, and L. Cordaro, “Two-year prospective clinical comparison of immediate replacement vs. immediate restoration of single tooth in the esthetic zone,” Clinical Oral Implants Research, vol. 19, no. 11, pp. 1148–1153, 2008. View at Publisher · View at Google Scholar · View at Scopus
  17. M. Migliorati, L. Amorfini, A. Signori, A. S. Biavati, and S. Benedicenti, “Clinical and aesthetic outcome with post-extractive implants with or without soft tissue augmentation: a 2-year randomized clinical trial,” Clinical Implant Dentistry and Related Research, vol. 17, no. 5, pp. 983–995, 2015. View at Publisher · View at Google Scholar · View at Scopus
  18. S. Yoshino, J. Y. K. Kan, K. Rungcharassaeng, P. Roe, and J. L. Lozada, “Effects of connective tissue grafting on the facial gingival level following single immediate implant placement and provisionalization in the esthetic zone: a 1-year randomized controlled prospective study,” The International Journal of Oral & Maxillofacial Implants, vol. 29, no. 2, pp. 432–440, 2014. View at Publisher · View at Google Scholar · View at Scopus
  19. A. Edel, “The use of a connective tissue graft for closure over an immediate implant covered with occlusive membrane,” Clinical Oral Implants Research, vol. 6, no. 1, pp. 60–65, 1995. View at Publisher · View at Google Scholar · View at Scopus
  20. U. Covani, S. Marconcini, G. Galassini, R. Cornelini, S. Santini, and A. Barone, “Connective tissue graft used as a biologic barrier to cover an immediate implant,” Journal of Periodontology, vol. 78, no. 8, pp. 1644–1649, 2007. View at Publisher · View at Google Scholar · View at Scopus
  21. S. G. Jyothi, M. G. Triveni, D. S. Mehta, and K. Nandakumar, “Evaluation of single-tooth replacement by an immediate implant covered with connective tissue graft as a biologic barrier,” Journal of Indian Society of Periodontology, vol. 17, no. 3, pp. 354–360, 2013. View at Publisher · View at Google Scholar · View at Scopus
  22. W. Becker, C. Dahlin, B. E. Becker et al., “The use of e-PTFE barrier membranes for bone promotion around titanium implants placed into extraction sockets: a prospective multicenter study,” The International Journal of Oral & Maxillofacial Implants, vol. 9, no. 1, pp. 31–40, 1994. View at Google Scholar · View at Scopus
  23. P. A. Fugazzotto, “Maintaining primary closure after guided bone regeneration procedures: introduction of a new flap design and preliminary results,” Journal of Periodontology, vol. 77, no. 8, pp. 1452–1457, 2006. View at Publisher · View at Google Scholar · View at Scopus
  24. F. Khoury and A. Hoppe, “Soft tissue management in oral implantology: a review of surgical techniques for shaping an esthetic and functional peri-implant soft tissue structure,” Quintessence International, vol. 31, no. 7, pp. 483–499, 2000. View at Google Scholar · View at Scopus
  25. C. E. Nemcovsky, Z. Artzi, and O. Moses, “Rotated split palatal flap for soft tissue primary coverage over extraction sites with immediate implant placement. Description of the surgical procedure and clinical results,” Journal of Periodontology, vol. 70, no. 8, pp. 926–934, 1999. View at Publisher · View at Google Scholar · View at Scopus
  26. C. E. Nemcovsky, Z. Artzi, and O. Moses, “Rotated palatal flap in immediate implant procedures: clinical evaluation of 26 consecutive cases,” Clinical Oral Implants Research, vol. 11, no. 1, pp. 83–90, 2000. View at Google Scholar · View at Scopus
  27. D. S. Thoma, B. Buranawat, C. H. F. Hämmerle, U. Held, and R. E. Jung, “Efficacy of soft tissue augmentation around dental implants and in partially edentulous areas: a systematic review,” Journal of Clinical Periodontology, vol. 41, no. 15, supplement, pp. S77–S91, 2014. View at Publisher · View at Google Scholar · View at Scopus
  28. L. Poskevicius, A. Sidlauskas, P. Galindo-Moreno, and G. Juodzbalys, “Dimensional soft tissue changes following soft tissue grafting in conjunction with implant placement or around present dental implants: a systematic review,” Clinical Oral Implants Research, 2015. View at Publisher · View at Google Scholar · View at Scopus
  29. M. Esposito, M. G. Grusovin, I. P. Polyzos, P. Felice, and H. V. Worthington, “Interventions for replacing missing teeth: dental implants in fresh extraction sockets (immediate, immediate-delayed and delayed implants),” Cochrane Database of Systematic Reviews, vol. 8, no. 9, Article ID CD005968, 2010. View at Google Scholar · View at Scopus
  30. D. Moher, D. G. Altman, A. Liberati, and J. Tetzlaff, “PRISMA statement,” Epidemiology, vol. 22, no. 1, p. 128, 2011. View at Publisher · View at Google Scholar · View at Scopus
  31. D. O'Connor, S. Green, and J. P. T. Higgins, “Chapter 5: defining the review question and developing criteria for including studies,” in Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0, J. P. T. Higgins and S. Green, Eds., The Cochrane Collaboration, London, UK, 2011, http://www.cochrane-handbook.org/. View at Google Scholar
  32. M. C. Fagan, H. Owens, J. Smaha, and R. T. Kao, “Simultaneous hard and soft tissue augmentation for implants in the esthetic zone: report of 37 consecutive cases,” Journal of Periodontology, vol. 79, no. 9, pp. 1782–1788, 2008. View at Publisher · View at Google Scholar · View at Scopus
  33. S. Reinhardt, “Immediate implants with a simultaneous soft-tissue graft—2 years results of a new technique,” Zeitschrift für Zahnärztliche Implantologie, vol. 28, no. 3, pp. 240–247, 2012. View at Publisher · View at Google Scholar · View at Scopus
  34. K. Rungcharassaeng, J. Y. K. Kan, S. Yoshino, T. Morimoto, and G. Zimmerman, “Immediate implant placement and provisionalization with and without a connective tissue graft: an analysis of facial gingival tissue thickness,” The International Journal of Periodontics & Restorative Dentistry, vol. 32, no. 6, pp. 657–663, 2012. View at Google Scholar · View at Scopus
  35. R. Cornelini, A. Barone, and U. Covani, “Connective tissue grafts in postextraction implants with immediate restoration: a prospective controlled clinical study,” Practical Procedures & Aesthetic Dentistry, vol. 20, no. 6, pp. 337–343, 2008. View at Google Scholar · View at Scopus
  36. Y.-M. Lee, D.-Y. Kim, J. Y. Kim et al., “Peri-implant soft tissue level secondary to a connective tissue graft in conjunction with immediate implant placement: a 2-year follow-up report of 11 consecutive cases,” The International Journal of Periodontics and Restorative Dentistry, vol. 32, no. 2, pp. 213–222, 2012. View at Google Scholar · View at Scopus
  37. J. Y. K. Kan, K. Rungcharassaeng, T. Morimoto, and J. Lozada, “Facial gingival tissue stability after connective tissue graft with single immediate tooth replacement in the esthetic zone: consecutive case report,” Journal of Oral and Maxillofacial Surgery, vol. 67, no. 11, supplement, pp. 40–48, 2009. View at Google Scholar · View at Scopus
  38. J. Y. K. Kan, K. Rungcharassaeng, A. Sclar, and J. L. Lozada, “Effects of the facial osseous defect morphology on gingival dynamics after immediate tooth replacement and guided bone regeneration: 1-year results,” Journal of Oral and Maxillofacial Surgery, vol. 65, no. 7, pp. 13–19, 2007. View at Publisher · View at Google Scholar · View at Scopus
  39. H. Tsuda, K. Rungcharassaeng, J. Y. K. Kan, P. Roe, J. L. Lozada, and G. Zimmerman, “Peri-implant tissue response following connective tissue and bone grafting in conjunction with immediate single-tooth replacement in the esthetic zone: a case series,” The International Journal of Oral & Maxillofacial Implants, vol. 26, no. 2, pp. 427–436, 2011. View at Google Scholar · View at Scopus
  40. S. Chung, K. Rungcharassaeng, J. Y. K. Kan, P. Roe, and J. L. Lozada, “Immediate single tooth replacement with subepithelial connective tissue graft using platform switching implants: a case series,” Journal of Oral Implantology, vol. 37, no. 5, pp. 559–569, 2011. View at Publisher · View at Google Scholar · View at Scopus
  41. J. P. T. Higgins and S. Green, Cochrane Handbook for Systematic Reviews of Interventions, Version 5.1.0, The Cochrane Collaboration, 2011.
  42. M. G. Araújo and J. Lindhe, “Dimensional ridge alterations following tooth extraction. An experimental study in the dog,” Journal of Clinical Periodontology, vol. 32, no. 2, pp. 212–218, 2005. View at Publisher · View at Google Scholar · View at Scopus
  43. I. J. De Kok, S. S. Chang, J. D. Moriarty, and L. F. Cooper, “A retrospective analysis of peri-implant tissue responses at immediate load/provisionalized microthreaded implants,” International Journal of Oral and Maxillofacial Implants, vol. 21, no. 3, pp. 405–412, 2006. View at Google Scholar · View at Scopus
  44. L. Den Hartog, J. J. R. Huddleston Slater, A. Vissink, H. J. A. Meijer, and G. M. Raghoebar, “Treatment outcome of immediate, early and conventional single-tooth implants in the aesthetic zone: a systematic review to survival, bone level, soft-tissue, aesthetics and patient satisfaction,” Journal of Clinical Periodontology, vol. 35, no. 12, pp. 1073–1086, 2008. View at Publisher · View at Google Scholar · View at Scopus
  45. D. Moher, S. Hopewell, K. F. Schulz et al., “CONSORT 2010 explanation and elaboration: updated guidelines for reporting parallel group randomised trials,” British Medical Journal, vol. 340, article c869, 2010. View at Publisher · View at Google Scholar · View at Scopus
  46. E. von Elm, D. G. Altman, M. Egger, S. J. Pocock, P. C. Gøtzsche, and J. P. Vandenbroucke, “The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement: guidelines for reporting observational studies,” The Lancet, vol. 370, no. 9596, pp. 1453–1457, 2007. View at Publisher · View at Google Scholar · View at Scopus