The aim of the present study was to analyze the survival and success rates of dental implants placed in atrophic alveolar ridges reconstructed with mandibular symphysis autogenous onlay bone grafts, with a 20-year follow-up. A sample of five patients referred to the authors' department between 2000 and 2001 seeking for an implant-supported fixed rehabilitation. Patients were treated by means of autogenous bone blocks grafted from the mandibular symphysis and covered with bone substitutes (DBB) and a resorbable membrane. Then delayed implants were placed and finally prosthetic restoration was performed. In total, 10 implants placed in 5 patients were evaluated with a follow-up of 20 years. Both implant survival and success rate were 100%. The mean marginal bone loss was 0.32 [[EQUATION]] 0.39 mm (range 0-1.3 mm). Considering the conditions of peri-implant hard and soft tissues, the diagnosis of peri-implant health was made for all the implants included. According to this study, implants placed in alveolar ridges augmented by means of autogenous chin bone grafts showed long-term survival and high success rates. A correct management of peri-implant soft tissues and an accurate prosthetic rehabilitation are also fundamental to obtain the durable success of the treatment.
Keywords: Alveolar bone atrophies, bone regeneration, onlay bone grafting, mandibular symphysis, alveolar bone loss, peri-implant health.