Comparative evaluation of crestal bone loss around platform-switched and platform-matched implants: A prospective radiographic study

Abstract

Marginal crestal bone stability influences the long-term biological and esthetic success of implant-supported restorations, while the benefit of platform switching may depend on implant design, tissue thickness and restorative geometry. Therefore, it is of interest to compare the peri-implant crestal bone loss around platform-switched and platform-matched implants during the first year of functional loading in 60 participants randomized equally between the two restoration designs. Standardized digital periapical radiographs were obtained at prosthesis delivery, 6 months and 12 months and mesial/distal marginal bone levels, probing depth, bleeding on probing and implant survival were evaluated. Mean 12-month marginal bone loss was 0.58 ± 0.24 mm with platform switching and 1.12 ± 0.35 mm with platform matching (p<0.001); the difference remained significant after adjustment for implant site, mucosal thickness and insertion depth, while implant survival was 100% and 96.7%, respectively. Thus, platform switching was associated with high preservation of crestal bone during the first year of loading, while peri-implant soft-tissue outcomes were comparable.