Marginal bone loss around implants with platform switching and platform matched connection: A systematic review

Statement of problem: Platform switching using narrower abutments than the implant platform has been used to reduce marginal bone loss (MBL) surrounding dental implants. While platform switching has been reported to prevent initial peri-implant bone loss, available data regarding the use of the platform-switching implant abutment configuration with long-term follow-up has been sparse; thus, the systematic review was planned to evaluate the best available evidence for the use of the platform switching technique.

Purpose: The purpose of this systematic review was to answer the specific question, "Is there a difference between platform-matching implant abutment configurations and platform-switching implant abutment configurations in terms of MBL changes around endosseous implants"?

Material and methods: The PubMed/Medline, Scopus, Google Scholar, and Lilac databases were searched by 2 independent reviewers for articles published between January 2000 and July 2022. Platform-switched versus platform-matched implants were examined for changes in MBL in human randomized clinical trials (RCTs) and potential clinically controlled cohort studies (PCCS).

Results: Overall, 4 eligible studies were included and critically evaluated to summarize their findings. The follow-up period of the included studies was between 5 and 10 years. Two of the included studies showed a mean ±standard deviation of 0.6 ±0.20 mm MBL at 5 years and 1.20 ±0.21 mm at 10 years for the platform switched (PS) technique and 1.1 ±0.3 mm and 1.24 ±0.39 mm MBL for the platform matched (PM) technique. Another study showed marginal bone level changes for the platform-switched technique to be 0.18 ±0.14 mm as compared with the platform matched technique (0.80 ±0.40 mm). In one of the studies published in 2019, the mean estimated difference in the marginal bone levels of PS- and PM-restored implants after 5 years was reported to be 0.29 mm. The descriptive analysis of 4 RCTs indicated that platform-switched implant-to-abutment connections reduced average marginal bone loss surrounding implants compared with platform-matched implant-to-abutment connections, favoring the platform-switched approach.

Conclusions: Platform switching appears to be a beneficial approach for retaining the crestal bone around dental implants.