Success rates in subjects rehabilitated with immediate loading technique on according to AISI guidelines

Introduction. The aim of the work is to verify the success rates of the immediate load technique after 48 months, on subjects operated on according to AISI guidelines, and to identify key factors in successful surgery and main causes of failure. Materials and method. 62 patients rehabilitated with immediate load one-piece self-threading screws, in the period between January and November 2002. The subjects were checked clinically, by X-rays and through biomechanical analysis. Results. In seriated checkups and in the final check up four years after the operation, we found no subjective or objective symptoms, good stability and, after X-rays, a normal peri-implant bone. The implants satisfied the tests adopted with 98.4% success rate of subjects operated on and an implant survival rate of 99%. Discussion. Successful surgery presupposes the correct application of a validated protocol. Key success factors are patient selection, careful surgical planning, primary and secondary stability. The main cause of failure is identified as an incorrect prosthetic design.