Mandibular overdentures supported by two Branemark, IMZ or ITI implants:a ten-year prospective randomized study

ObjectivesThe aim of this prospective comparative study was to evaluate the survival rate, condition of peri-implant tissues, patient satisfaction and surgical and prosthetic aftercare of the IMZ-implant system (two-stage cylinder type), the Branemark-implant system (two-stage screw type) and the ITI-implant system (one-stage screw type) supporting a mandibular overdenture during a 10-year follow-up period.Materials and MethodsThree groups of 30 edentulous patients were treated with two endosseous implants in the interforaminal region of the mandible. Clinical and radiographic parameters were evaluated immediately after completion of the prosthetic treatment and after 1, 5 and 10 years of functional loading. Prosthetic and surgical aftercare was scored during the evaluation period, as well as patient satisfaction.ResultsThe 10-year survival rate was 93% for the IMZ group, 98% for the Branemark group and 100% for the ITI group (IMZ <ITI, p <0.05). Mean marginal bone loss was limited over a period of 10 years. No differences in satisfaction and aftercare were observed between the groups.ConclusionIt is concluded that two implants placed in the interforaminal region, connected with a bar, supply a proper base for the support of a mandibular overdenture in the edentulous patient. After10 years, no relevant changes had developed between the three implant systems.