Baek Seung-Hak, Ahn Hyo-Won, Kwon Yoon-Hee, Choi Jin-Young
Department of Orthodontics, School of Dentistry, Dental Research Institute, Seoul National University, Seoul, South Korea.
J Craniofac Surg. 2010 Mar;21(2):332-8. doi: 10.1097/SCS.0b013e3181cf5fd4.
The purpose of this study was to evaluate the surgical movement and postoperative orthodontic treatment (POT) of the surgery-first approach for the correction of skeletal class III malocclusion. The samples consisted of 11 patients with skeletal class III malocclusion who underwent nonextraction treatment and 2-jaw surgery (Le Fort I osteotomy impaction of the posterior maxilla, IPM; bilateral sagittal split ramus osteotomy setback of the mandible). The wafer was removed 4 weeks after surgery. Mean (SD) durations of POT and total treatment were 8.91 (3.14) and 12.18 (3.57) months, respectively. Lateral cephalograms were obtained during the initial examination (T0), immediately after surgery (T1), and after debonding (T2). Sixteen variables were measured. Paired t-test was performed for statistical analysis. The maxilla rotated clockwise, and the nasolabial angle increased by IPM (FH-palatal plane angle, FH-occlusal plane angle, P < 0.01; nasolabial angle, P < 0.05) and well maintained during POT. The mandible was repositioned backward by bilateral sagittal split ramus osteotomy setback of the mandible (SNB, Pog-N perp, P < 0.001) and relapsed forward during POT (SNB, P < 0.01; Pog-N perp, P < 0.05). U1-SN decreased by IPM (P < 0.001) and relapsed labially owing to class III mechanics during POT (P < 0.01); eventually, no significant difference was found between T0 and T2 stages. Although IMPA increased by POT, there was no significant difference between T0 and T2 stages. The mandible seems to relapse forward immediately after wafer removal and before labioversion of the lower incisors. Accurate prediction of POT is crucial in controlling dental alignment, incisor decompensation, arch coordination, and occlusal settling. Long-term wearing and selective grinding of the wafer for labioversion of the lower incisors and use of miniplates/miniscrews to control the inclination of the upper incisor and to prevent relapse of the mandible are needed.
本研究的目的是评估手术优先矫治骨性III类错牙合的手术移动及术后正畸治疗（POT）情况。样本包括11例接受非拔牙治疗及双颌手术（上颌后份Le Fort I型截骨前徙术，IPM；双侧下颌升支矢状劈开截骨后退术）的骨性III类错牙合患者。术后4周拆除咬合板。POT及总治疗的平均（标准差）时长分别为8.91（3.14）个月和12.18（3.57）个月。在初始检查（T0）、术后即刻（T1）及拆除矫治器后（T2）获取头颅侧位片。测量16个变量。采用配对t检验进行统计分析。通过IPM上颌顺时针旋转，鼻唇角增大（FH-腭平面角、FH-牙合平面角，P<0.01；鼻唇角，P<0.05）且在POT期间保持良好。通过双侧下颌升支矢状劈开截骨后退术使下颌向后复位（SNB、Pog-N垂线，P<0.001），且在POT期间向前复发（SNB，P<0.01；Pog-N垂线，P<0.05）。U1-SN通过IPM减小（P<0.001），且在POT期间由于III类矫治力学唇向复发（P<0.01）；最终，T0和T2阶段未发现显著差异。尽管POT使IMPA增大，但T0和T2阶段未发现显著差异。下颌在拆除咬合板后及下切牙唇倾前似乎立即向前复发。准确预测POT对于控制牙齿排列、切牙去代偿、牙弓协调及咬合稳定至关重要。需要长期佩戴并选择性打磨咬合板以使下切牙唇倾，以及使用微型钛板/微螺钉控制上切牙倾斜度并防止下颌复发。
