| Open bites are difficult malocclusions to treat both surgically and orthodontically. Numerous surgical techniques have been proposed in the literature for open bite correction, all with the common goal of restoring facial and occlusal balance and enhancing facial aesthetics while producing a stable result. Many studies and opinions exist regarding the best method of treating skeletal open bites. There seems to be a common consensus among clinicians that maxillary LeFort I osteotomy, with or without mandibular osteotomy, provides the most stable and predictable result (Epker and Fish, 1977). Proffit et al. (2007), proposed a hierarchy of orthognathic procedures in terms of stability. According to their study, superior repositioning of the maxilla is a highly stable procedure followed by bimaxillary procedures, which are considered stable with rigid fixation. In certain instances however, patients with anterior open bite present with an ideally positioned maxilla and maxillary surgery would actually be a detriment to the overall facial balance and harmony. In these select cases, the surgeon and orthodontist are confronted with a dilemma; whether to preserve maxillary position through using an alternative surgical approach, mandibular osteotomies alone. The latter had previously been abandoned in favor of maxillary osteotomy due to reported relapse prior to the advent of rigid fixation.;The aim of this study was to assess the stability of bilateral sagittal split osteotomies and closing rotation of the mandible with rigid fixation (2 mm bicortical screws) using cephalometric analysis. Twenty-eight patients who had completed orthodontic treatment and were at least one-year post surgery were evaluated by cephalometric analysis for dental and skeletal changes. Seven angular and six linear measurements were evaluated cephalometrically at three time points for each patient: immediately preoperatively (T1), immediate post operatively (T2), and after a minimum of one year postsurgical follow-up (T3). Twelve patients exhibited some degree of opening rotation from 1% to 64% with a mean of 16%. The remaining 16 patients showed no opening rotation or continued closure.;In a systematic review of anterior open bite correction by Huang (2002), treatment success was determined by positive overbite immediately post-surgery and a stable result was defined as positive incisal overlap at the last time point observed. All patients showed positive overbite at T3 indicating that even though skeletal relapse was observed post-surgically, dental compensatory mechanisms maintained the post-surgical occlusal relationships. Therefore, it can be concluded that bilateral sagittal split osteotomies and closing rotation of the mandible with the use of rigid fixation is a relatively stable procedure and a viable surgical treatment option in the correction of anterior open bites. |
