Augmented Corticotomy Combined With Accelerated Orthodontic Forces in Class III Orthognathic Patients: Morphologic Aspects of the Mandibular Anterior Ridge With Cone-Beam Computed Tomography

Abstract

This study used cone-beam computed tomography to evaluate morphologic changes of the mandibular anterior ridge after using augmented corticotomy plus accelerated orthodontia to decompensate mandibular incisors in patients with surgical skeletal Class III. Fourteen patients (8 men, 6 women; mean age, 26.14 yr) with skeletal Class III were treated before orthognathic surgery with a technique that combined corticotomy, bone grafting, and accelerated orthodontic forces to decompensate the lower incisors. Three-dimensional cone-beam computed tomograms were taken before treatment (T0) and at the completion of presurgical orthodontic treatment (T1). Measurements of the amount of vertical alveolar bone changes and horizontal bone thickness at the midroot and root apex levels of the mandibular incisors were evaluated. All patients showed significant proclination of the mandibular incisors at T1. The mean alveolar bone thickness from T0 to T1 increased buccally at the midroot and apex levels, showing statistically significant horizontal bone augmentation at the labial side of the lower anterior mandibular teeth (P < .05). The mean amount of vertical bone change did not show any significant vertical loss of alveolar bone. This new combined technique provided adequate decompensation of the mandibular incisors by increasing horizontal bone thickness in the labial aspect of the mandibular anterior area, without any vertical bone loss. This approach decreases the risk of the typical periodontal complications associated with traditional orthodontics, such as marginal bone loss and gingival recession.