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.