Implant-Supported Mandibular Overdentures Can Minimize Mandibular Bone Resorption in Edentulous Patients: Results of a Long-Term Radiologic Evaluation

Purpose: It has been suggested that functional loading and light irritative stimuli could lead to changes in bone architecture, shape, and volume, and that by placing implants in the edentulous mandible and subsequently loading them, functional conditions could be created to limit bone resorption or even stimulate bone apposition (the latter was reported only for fixed implant-supported prosthetic reconstructions) in the distal area of the mandibular osseous crest. The aim of this study was to radiographically assess the bone height changes in the posterior area of the mandible after implant placement and loading with an overdenture on two or four implants over a mean follow-up period of 10.5 years. Materials and Methods: Panoramic radiographs were taken of 82 totally edentulous patients before implant placement and at repeated follow-up intervals spread over a mean observation time of 10.5 years. All patients received an implant-supported overdenture as prosthetic treatment. The mandibular bone height in the distal part of the mandible was measured on each of the available radiographs and the initial, intermediate, and final values were compared. Results: A mean mandibular bone height reduction of 0.5 mm was measured. Conclusion: No clinically relevant difference was found between the posterior mandible height before implant placement and at follow-up after functional loading with an implant-supported mandibular overdenture. Keywords: bone height changes, implant-supported overdenture, radiographic assessment