Alveolar distraction osteogenesis for the correction of vertically deficient edentulous ridges: a multicenter prospective study on humans.

PURPOSE: The purposes of this prospective multicenter study were to evaluate the use of vertical distraction osteogenesis in the correction of vertically deficient alveolar ridges and to evaluate whether the vertical bone gained by distraction osteogenesis was maintained over time when dental implants were placed in the distracted areas. MATERIALS AND METHODS: Thirty-seven patients presenting vertically deficient edentulous ridges were treated in 4 different centers by means of distraction osteogenesis with an intraoral alveolar distractor. Two to 3 months after consolidation of the distracted segments, 138 dental implants were placed in the distracted areas. Four to 6 months later, abutments were connected and prosthetic loading of the implants began. RESULTS: The mean follow-up after initial prosthetic loading was 34 months (range 15 to 55 months). The mean bone gain obtained by distraction was 9.9 mm (range 4 to 15 mm). The cumulative success rate of the implants 4 years after the onset of prosthetic loading was 94.2%, while the implants' cumulative survival rate was 100%. No statistically significant differences were found between the different centers as far as survival and success rates of implants were concerned. DISCUSSION AND CONCLUSION: The results of this study appear to demonstrate that distraction osteogenesis is a reliable technique for the correction of vertically deficient edentulous ridges. The regenerated bone appeared to withstand the functional demands of implant loading. The survival and success rates of the implants placed in the distracted areas were consistent with those reported in the literature regarding implants placed in native bone in this patient population.