Platform switching: A step away from the gap

To maintain long-term stability of dental implants, it is important to minimize bone loss around an implant. Several clinical studies have shown a mean crestal bone loss of 1.5-2 mm around dental implants, in the first year after prosthetic restoration, as clinically acceptable. To limit this crestal bone resorption, several modifications are being tried in the implant systems. Platform Switching is one such concept, which uses prosthetic abutments with reduced diameter in relation to the implant platform diameter. This moves the implant abutment junction and supposedly the inflammatory reaction medially, away from the crestal bone, and may thus, minimize the crestal bone loss. Although, it was a serendipitous finding, an increasing number of implant systems have incorporated Platform Switching into their designs, as an innovative feature for preserving the peri-implant bone. A Medline search was carried out using the Pubmed search engine, with keywords Platform Switching in Dental Implants. Twenty-one studies (12 random-controlled trials, fourprospective-controlled clinical studies, and five clinical case series) were selected for review after screening of a total of 123 articles on the basis of the inclusion and exclusion criteria. A detailed review of these articles gave a clear tendency toward the positive impact of Platform Switching on crestal bone preservation, but further long-term, randomized-controlled trials, with uniform criteria, are required to confirm these results.

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