Peri-implant bone level around implants with platform-switched abutments.

PURPOSE The purpose of this clinical trial was to evaluate whether the crestal bone height around dental implants could be influenced by the use of a platform-switching protocol. MATERIALS AND METHODS All implants placed in the year 2006 in healed bone without any need for ridge augmentation were included in this study. The following groups were created: (1) wide-diameter implants were placed subcrestally and regular-diameter cover screws were connected; (2) regular-diameter implants were placed at the crest and regular-diameter cover screws were connected. Standardized radiographs were obtained after insertion of the definitive prosthesis and after 1 year. Calibrated measurements were conducted initiating from the mesial and distal bone peaks to the implant-abutment junction. The average value of the mean medial and mean distal values was calculated and analyzed with an unpaired two-tailed t test. P values < .05 were regarded as statistically significant. RESULTS In all, 89 dental implants in 36 patients were evaluated. The implants with a platform-switched configuration (n = 75) exhibited statistically significantly less bone loss at time of insertion of the definitive prosthesis (0.30 +/- 0.07 mm versus 0.68 +/- 0.17 mm; P < .05) and at 1 year (0.39 +/- 0.07 mm versus 1.00 +/- 0.22 mm, P < .01) when compared to the nonplatform-switched implants (n = 14). CONCLUSION Platform-switched implants seem to limit crestal bone remodeling.