전치부 개교합 환자의 하악지시상분할골절단술 후 수직적 안정성에 관한 연구

THE STUDY ON VERTICAL STABILITY OF ANTERIOR OPEN BITE PATIENTS AFTER BSSRO

Purpose The purpose of this study was to investigate the vertical stability after BSSRO surgery in skeletal class III malocclusion patients with mild anterior open bite and to present a method to increase the stability. Materials and methods 36 patients, 11 male and 25 female, who received BSSRO surgery with the diagnosis of skeletal class III with anterior open bite at the Department of Oral and Maxillofacial Surgery in Samsung Medical Center, from January 2002 to August 2003, were selected for this study. The patients were between 18 to 45 years of age. Preoperative and postoperative (immediate, 6 months, and 1 year after operation) lateral cephalograms were compared to evaluate the vertical stability by measuring the distance of nasion-menton, mandibular plane angle, and overbite. Results The nasion-menton distance decreased by 1.65mm immediately after the operation in comparison to the preoperative value. This distance further decreased by 0.60 mm at 6 months and 1.06mm at 1 year after the operation. The mandibular plane angle increased after the operation and further increased at 6 months and 1 year. The amount of overbite increased by the operation was 2.34mm and an additional increase of 0.70mm at 6 months and 0.94mm at 1 year were shown. Conclusion Clinically, none of the patients showed relapse of anterior open bite and the vertical stability is highly influenced by orthodontic treatment after the operation. In this study, BSSRO surgery is considered to be a rather reliable procedure that restores stability to skeletal class Ⅲ malocclusion patients with slight anterior open bite.