Professor Chonnam National University, School of Dentistry Gwangju, Kwangju-jikhalsi, Republic of Korea
Disclosure(s):
Kyungmin C. Lee, PhD: No financial relationships to disclose
Abstract:
Purpose: The present study aimed to investigate the effect of postoperative orthodontic treatment using clear aligners on the surgical stability in patients with mandibular prognathism. Patients and methods: This retrospective study included 30 patients with mandibular prognathism who underwent surgical orthodontic treatment and isolated mandibular setback surgery. The patients were divided into 2 groups according to the mechanic of postoperative orthodontic treatment after surgery; CA group included 15 patients treated with clear aligners during postoperative orthodontic treatment, and FA group included 15 patients treated with fixed appliances during postoperative orthodontic treatment. Cone-beam computed tomography scans were obtained before surgery (T0), immediately after surgery (T1), 3 months after surgery (T3), and 6 months after surgery (T6), and 1 year after surgery (T12). The measurements of postsurgical mandibular relapse including horizontal and vertical positions were compared according to the treatment progress and groups.
Results: The mandible was set back 7.7 ± 5.1 mm and 7.7 ± 5.1 mm at pogonion immediately after surgery in CA and FA group, respectively. Postsurgical skeletal relapse was 1.1 mm at pogonion during short-term follow-up. During long-term follow-up, the mandible moved 0.4 mm anteriorly, which was about 50% of the changes during short-term follow-up. (There were no significant differences in postoperative skeletal relapse) Statistically significant correlations were found in postsurgical skeletal relapse between CA and FA groups. However, in the CA group, the postoperative skeletal relapse was larger than in the FA group. Both fixed orthodontic appliances and clear aligner treatment patients showed similar postoperative mandibular relapse.
Conclusion: Although there were no statistically significant differences in surgical relapse between both groups, clear aligner treatment group showed larger relapse tendency than fixed appliance treatment group. Careful consideration is needed in the postoperative management of patients treated with clear aligner and surgery-first orthognathic treatment.
