Use of cone-beam computed tomography for investigation of factors affecting the failure of temporary anchorage devices.

Purpose: To assess the reasons behind the failure of temporary anchorage devices (TADs) installed in the buccal alveolar zone between the maxillary second premolars and the first molars.

Methods: Sixty patients (11 male, 49 female, mean age 21 years) were included. Logistic regression analysis was performed to determine the influence of the following factors on the presence or absence of TAD failure: sex, age, sagittal and vertical skeletal patterns, root contact, bone density, bone contact length, and presence of maxillary sinus perforation. Fisher's exact test was performed to evaluate differences in failure rate between tooth types for teeth in contact with TADs (second premolar or first molar). Measurements were obtained using lateral cephalograms at the initial visit and data obtained by cone-beam computed tomography (CBCT) before and after TAD implantation.

Results: Logistic regression analysis showed that only root contact was associated with TAD failure; there was no association between the type of tooth in contact with the TAD and failure.

Conclusion: Root contact with a TAD significantly influenced TAD failure. Therefore, preliminary examination using three-dimensional (3D) evaluation with CBCT is essential to ensure that the TAD is not placed near the root of the tooth.