A prospective study of single stage surgery for implant supported overdentures

Objectives: To investigate the clinical and psychological outcomes with ball attachment supported mandibular overdentures on Branemark implants placed in a single stage surgical approach. Material and method: Sixteen edentulous patients aged 32-74, with atrophic (flat) mandibular residual alveolar ridges, and a history of having difficulty coping with technically adequate mandibular dentures made within the last 2 years were recruited. Mark 11 Branemark implants were placed using a single stage surgical technique with healing abutments placed at time of surgery. Mandibular complete dentures were modified by relieving the areas over the abutments and a resilient liner was placed. After a period of 3 months, healing abutments were replaced with ball abutments and new complete dentures were made and the patients followed for a period of 2 years. Patients completed the General Health Questionnaire (GHQ) and answered further questions relating to the functional and psychological impact of complete denture wearing before treatment and 3 months after the dentures were provided. Patients additionally completed the GHQ 2 years after overdenture insertion. Results: Six patients suffered from loss of one of their two implants in the f irst: 2 years after placement. Three of the implants had failed to osseointegrate, which was detected at initial loading 3 months after placement. General Health Questionnaire scores were statistically significantly reduced after treatment and the improvement was maintained over 2 years. Responses to the functional and psychological questions were similarly improved. Conclusion: Single stage surgery led to a higher rate of implant failure than expected. Patients showed significant psychological health benefits from the treatment provided.