Table of Contents
Journal of Dental Surgery
Volume 2014 (2014), Article ID 685803, 7 pages
Clinical Study

Factors Associated with Bone Level Alterations at Implants with Inner-Cone Connection and Platform Switching

1Department of Prosthodontics, University of Bern, Freiburgstrasse 7, 3010 Bern, Switzerland
2Department of Periodontology, University of Bern, Freiburgstrasse 7, 3010 Bern, Switzerland

Received 19 December 2013; Accepted 15 January 2014; Published 23 February 2014

Academic Editor: Luis Manuel Junquera Gutierrez

Copyright © 2014 Renzo Bassetti 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.


Purpose. This retrospective cohort study evaluated factors for peri-implant bone level changes (ΔIBL) associated with an implant type with inner-cone implant-abutment connection, rough neck surface, and platform switching (AT). Materials and Methods. All AT placed at the Department of Prosthodontics of the University of Bern between January 2004 and December 2005 were included in this study. All implants were examined by single radiographs using the parallel technique taken at surgery (T0) and obtained at least 6 months after surgery (T1). Possible influencing factors were analysed first using t-test (normal distribution) or the nonparametric Wilcoxon test (not normal distribution), and then a mixed model q variance analysis was performed. Results. 43 patients were treated with 109 implants. Five implants in 2 patients failed (survival rate: 95.4%). Mean ΔIBL in group 1 (T1: 6–12 months after surgery) was  mm and  mm in group 2 (T1: >12 months after surgery) ( ). Greater implant insertion depth in diameter 3.5 mm implants might be associated with increased ΔIBL ( ). In the anterior region, the bone alteration was more pronounced ( ). Conclusions. ΔIBL values indicated that the implant system used in this study fulfilled implant success criteria.