Complications in alveolar distraction osteogenesis of the atrophic mandible.

To improve the starting point for placement of dental implants, 45 patients suffering from atrophied edentulous mandibles, with a vertical height varying between 7.3 and 15.8mm, were treated by alveolar vertical distraction osteogenesis (VDO). The mean follow-up period was 3 years, ranging from 1 to 7 years. Associated complications, as occurred during instalment of the distractor device, VDO period and consolidation phase, and also after dental implant placement, were evaluated. Observed complications were: early fractures (2%), late fractures (17%), bleeding or haematoma (4%), infections (6%), skin perforation (2%), mucosal dehiscence (8%), sensory disturbances (28%), sagging chin (13%) and failure of dental implants (13%). In 10 patients 2 complications and in 1 patient 3 complications were monitored. All complications occurred in the first year. It is concluded that VDO to restore vertical bone height in patients with mandibular atrophy is a surgically delicate technique with a high risk of various complications. The likelihood of the most striking complication, namely fracture occurrence, increases with decreasing residual bone height.