Bone density effects on the success rate of orthodontic microimplants evaluated with cone-beam computed tomography

Introduction: The purpose of this study was to evaluate the effect of bone densities on the success rate of orthodontic microimplants with cone-beam computed tomography images. Methods: We examined 127 orthodontic microimplants implanted into the maxillary buccal alveolar bone of 71 patients (53 female, 18 male; mean age, 19.2 years) with malocclusion. The cortical, cancellous, and total bone densities were measured with Simplant Pro 2011 software (version 13; Materialise, Leuven, Belgium), and the correlations between these measurements and the orthodontic microimplant success rates were evaluated with cone-beam computed tomography. Results: The overall success rate was 85.0% (108 of 127). Sex, age, and side of placement were not significant factors for success in the results (P > 0.05). The density of the cortical bone increased apically (3, 5, and 7 mm) from the alveolar crest, but in the cancellous bone it decreased. Whereas the orthodontic microimplant success rates significantly increased as cancellous bone density and total bone density increased (P < 0.01), cortical bone density did not have a significant effect on the success rate (P > 0.05). Conclusions: The success rate of orthodontic microimplants significantly increased with higher cancellous and total bone densities, whereas cortical bone density did not have a significant effect.