The goal of current dental implant treatment is more than just the successful Osseo integration of the implant. It includes an aesthetic and functional restoration surrounded by stable peri-implant tissue levels that are in harmony with the existing dentition, Crestal bone remodelling starts immediately after implant placement, Platform switching is a technique which can preserve the crestal bone loss. The purpose of this article is to carry out are view of studies dealing with the platform switching concept to preserve the Crestal bone, the mechanism by which it contributes to maintenance of biological width, how the stresses are distributed and influence of micro gap on Crestal bone loss.