Kim Chin-Soo, Lee Sang-Chang, Kyung Hee-Moon, Park Hyo-Sang, Kwon Tae-Geon
Professor, Department of Oral and Maxillofacial Surgery, School of Dentistry, Kyungpook National University, Daegu, Korea.
Resident, Department of Oral and Maxillofacial Surgery, School of Dentistry, Kyungpook National University, Daegu, Korea.
J Oral Maxillofac Surg. 2014 Apr;72(4):779-87. doi: 10.1016/j.joms.2013.09.033. Epub 2013 Oct 2.
The purpose of this study was to compare stability after mandibular setback surgery in patients with skeletal Class III malocclusion with and without presurgical orthodontics.
This retrospective cohort study included consecutive patients with skeletal Class III malocclusion who underwent only mandibular surgery. Patients treated with the surgery-first approach without presurgical orthodontics (SF group) were compared with a control group (conventional surgery with presurgical orthodontics; CS group) using lateral cephalograms taken preoperatively, immediately postoperatively, and at the time of debonding. Predictor variables (group and timing), outcome variables (cephalometric measurements over time), and other variables, such as baseline characteristics, were evaluated to determine the difference in stability of mandibular positions such as the B point.
Sixty-one patients were enrolled in this study (CS group, n = 38; SF group, n = 23). Baseline demographic variables were similar in the 2 groups except for orthodontic treatment period. The mean setback of the mandible at the B point was similar (CS group, 8.7 mm; SF group, 9.1 mm; difference, P > .05), but the horizontal relapse in the SF group (2.4 mm) was significantly greater than in the CS group (1.6 mm; P < .05). Patients with a horizontal relapse greater than 3 mm comprised 39.1% of the SF group compared with 15.8% of the CS group (P < .05).
Mandibular sagittal split ramus osteotomy without presurgical orthodontic treatment was less stable than conventional orthognathic surgery for mandibular prognathism. Before performing a surgery-first approach, skeletal stability needs to be considered.
本研究旨在比较接受下颌后缩手术的骨性III类错牙合患者在术前是否进行正畸治疗后的稳定性。
这项回顾性队列研究纳入了仅接受下颌手术的连续性骨性III类错牙合患者。将采用手术优先方法且未进行术前正畸治疗的患者（SF组）与对照组（术前正畸治疗后进行传统手术；CS组）进行比较，使用术前、术后即刻以及拆除矫治器时拍摄的头颅侧位片。评估预测变量（分组和时间）、结果变量（随时间的头影测量）以及其他变量，如基线特征，以确定下颌位置（如B点）稳定性的差异。
本研究共纳入61例患者（CS组，n = 38；SF组，n = 23）。除正畸治疗时间外，两组的基线人口统计学变量相似。B点处下颌的平均后缩量相似（CS组，8.7 mm；SF组，9.1 mm；差异，P >.05），但SF组的水平复发（2.4 mm）显著大于CS组（1.6 mm；P <.05）。水平复发大于3 mm的患者在SF组中占39.1%，而在CS组中占15.8%（P <.05）。
对于下颌前突，未进行术前正畸治疗的下颌升支矢状劈开截骨术比传统正颌手术的稳定性更差。在采用手术优先方法之前，需要考虑骨骼稳定性。
