OBJECTIVES: To use three-dimensional (3D) mirroring and surface-to-surface techniques to determine any differences in mandibular functional unit shape and morphology between the crossbite side and non-crossbite side in adult patients with posterior unilateral crossbite who had not received any corrective treatment for malocclusion.MATERIALS AND METHODS: Cone-beam computed tomography (CBCT) records from 24 consecutive adult white patients (mean age, 27.5 years; range 22.6-39.7 years; 14 women and 10 men) seeking treatment for maxillary transverse deficiency were assessed in this study. The control group comprised CBCT scans from age- and sex-matched patients. Segmentation masks were generated to obtain 3D surface mesh models of the mandibles and analyze the six skeletal functional units, which were further analyzed with reverse engineering software.RESULTS: Statistically significant differences in the mean surface distance when comparing the study sample and the control sample were found at the condylar process, mandibular ramus, angular process (P ? .0001), and alveolar process (P ? .01); no statistically significant differences were found for the coronoid process, the chin, and the mandibular body (P ? .5).CONCLUSIONS: The condylar, angular, and alveolar processes plus the mandibular ramus appear to play a more dominant role than did the body, the coronoid, and the chin units in the asymmetry of the mandible in patients with unilateral crossbite.
Adult Cone-Beam Computed Tomography