Researchers have attempted to explain the mechanism of action of platform switching; however, it is necessary to conduct further studies, including histological studies using animals, to clarify the mechanism fully. With respect to radiographic evaluations of crestal bone levels in humans, properly designed long- term observation is required, before establishing the long-term predictability of platform switching in preserving horizontal and vertical marginal bone levels or modifying the minimum distances between platform-switched implants and adjacent teeth or implants particularly through prospective, randomized, multicenter trials with large number of participants.