Choi Y J, Lim H, Chung C J, Park K H, Kim K H
Department of Orthodontics, Gangnam Severance Dental Hospital, College of Dentistry, The Institute of Craniofacial Deformity, Yonsei University, Seoul, Republic of Korea.
Clinical Research Management Team, National Health Insurance Service, Ilsan Hospital, Goyang, Gyeonggi, Republic of Korea.
Int J Oral Maxillofac Surg. 2014 Jun;43(6):742-7. doi: 10.1016/j.ijom.2014.02.005. Epub 2014 Mar 12.
This study was performed to examine the longitudinal changes in bite force and occlusal contact area after mandibular setback surgery via intraoral vertical ramus osteotomy (IVRO). Patients with mandibular prognathism who underwent IVRO (surgical group: 39 men and 39 women) were compared with subjects with class I skeletal and dental relationships (control group; 32 men and 35 women). The surgical group was divided into two subgroups: 1-jaw surgery (n = 30) and 2-jaw surgery (n = 48). Bite force and contact area were measured in maximum intercuspation with the Dental Prescale System before treatment, within 1 month before surgery, and at 1, 3, 6, 9, 12, and 24 months postsurgery. A linear mixed model was used to investigate the time-dependent changes and associated factors. Bite force and contact area decreased during presurgical orthodontic treatment, were minimal at 1 month postsurgery, and increased gradually thereafter. The 1-jaw and 2-jaw subgroups showed no significant differences in bite force. The time-dependent changes in bite force were significantly different according to the contact area (P < 0.05). The results of this study suggest that bite force and occlusal contact area gradually increase throughout the postsurgical evaluation period. Increasing the occlusal contact area may be essential for improving bite force after surgery.
本研究旨在通过口内垂直升支截骨术（IVRO）检查下颌后缩手术后咬合力和咬合接触面积的纵向变化。将接受IVRO的下颌前突患者（手术组：39名男性和39名女性）与骨骼和牙齿关系为I类的受试者（对照组；32名男性和35名女性）进行比较。手术组分为两个亚组：单颌手术（n = 30）和双颌手术（n = 48）。在治疗前、手术前1个月内以及术后1、3、6、9、12和24个月时，使用牙科预标度系统在最大牙尖交错位测量咬合力和接触面积。采用线性混合模型研究时间依赖性变化及相关因素。咬合力和接触面积在术前正畸治疗期间下降，术后1个月时最小，此后逐渐增加。单颌和双颌亚组的咬合力无显著差异。咬合力的时间依赖性变化根据接触面积有显著差异（P < 0.05）。本研究结果表明，在整个术后评估期内，咬合力和咬合接触面积逐渐增加。增加咬合接触面积可能是改善术后咬合力的关键。
