Effect of 3 vertical facial patterns on alveolar bone quality at selected miniscrew implant sites.

Abstract To evaluate dental alveolar bone quality among young healthy Chinese adults having 3 different vertical patterns. Three-dimensional cone-beam computed tomography images of 101 subjects (15 low-angle, 48 average-angle, and 38 high-angle) were reconstructed. Facial alveolar cortical bone thicknesses and cortical and cancellous bone densities at 4 selected miniscrew implant sites in both arches, together with cancellous bone densities of third cervical vertebrae, were measured. Bone qualities were compared among the 3 vertical pattern groups. The cortical bone thicknesses at mandibular 5-6 and 6-7 and the cortical and cancellous bone densities at maxillary and mandibular 5-6 and 6-7 were generally greater in the low-angle than in the other 2 groups. There was no similar consistent vertical pattern apparent for bone quality at the 1-1 and 1-2 sites. No significant differences in bone densities for third cervical vertebrae were found among the 3 groups. Careful selection of suitable implantation sites and sizes of the miniscrews used should be made to reduce the possible occurrence of implant loosening in patients with average-angle and high-angle vertical facial patterns in particular.