The rates for survival of implant-supported single- and multiple-tooth restorations are found comparable to those for implant-supported prostheses in completely edentulous patients. However, the goal of modern implant therapy is focused on more than just the successful osseointegration (survival) of the implant. A successful result must also provide an esthetic and functional restoration surrounded by sound peri-implant tissues that are in harmony with the existing dentition. Stable level of peri-implant bone is one set parameter of implant success. As a process to improve long-term bone maintenance around implants, a new implant-to-abutment connection referred to as "platform switching" was proposed. The resulting crestal bone levels around dental implants after the restoration has been a topic of discussion and used as a reference for evaluation of implant success for many years.