Influence of thin mucosal tissues on crestal bone stability around implants with platform switching: a 1-year pilot study.

PURPOSE: The aim of this pilot study was to determine what effect thin mucosal tissues can have on crestal bone stability around implants with platform switching.
MATERIALS AND METHODS: Twelve 2-piece implants, consisting of 6 implants with horizontally matching implant-abutment connection (control) and 6 implants with platform switching (test) were placed in 4 patients. The mean age of the patients was 43 years (range, 37 to 56 yrs). Mucosal tissue thickness at implant sites was measured to be 2 mm or less. Implants were restored with 5 splinted crowns and single 3-unit fixed partial denture. Intraoral radiographs were obtained and crestal bone changes were measured at implant placement and after a 1-year follow-up post-treatment. The statistical significance level was set to P less than .05.
RESULTS: Bone loss around the test implants was 1.81 +/- 0.39 mm on the mesial site and 1.70 +/- 0.35 mm on the distal aspect. Control implants overcame marginal bone resorption equaling 1.60 +/- 0.46 mm on the mesial site and 1.76 +/- 0.45 mm on distal measurement. No statistically significant difference was found between control and test implants either mesially (F([1,10]) = 0.746; P = .408) or distally (F([1,10]) = 0.080; P = .783).
CONCLUSION: Within the limitations of this pilot study it can be concluded that implants with platform switching did not preserve crestal bone better in comparison with implants with traditional implant-abutment connection if, at the time of implant placement, thin mucosal tissues were present. Copyright 2010 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.