The conventional placement protocol for submerged and non-submerged implants was proposed in the 1960s and 1970s. Multicenter studies have reported satisfactory success rates for both protocols and a similar loss of crestal peri-implant bone after implant loading (0.5 to 1.5 mm). In recent years, placement of submerged implants using a single surgical procedure was introduced, with the immediate placement of a healing abutment. Some studies reported good short-term results using this approach. Recently, a supracrestal apical-coronal positioning of the implant collar has been proposed for posterior sectors using submerged implants. This positioning facilitates the second surgical phase, as well as fabrication of the prosthetic restoration, and limits the amount of crestal bone loss.
Keywords: bone resorption, dental implants, endosseous dental implantation, preprosthetic oral surgical procedures