摘要
目的观察下颌角截骨术后咬肌形态的动态变化。方法采集120例下颌骨截骨受术者术前及术后3、6、12个月时头颅CT数据，并进行三维重建，通过软件平台设定合适的阈值范围，分割出咬肌组织。经过断层叠加创建咬肌的三维分割体，由软件输出咬肌体积等三维信息。再选定3处横截面，即A平面：过咬合平面水平，下颌升支前后缘中点的平面；B平面：A平面上1cm；C平面：A平面下1cm。在各横截面上测量咬肌的面积和厚度，观察咬肌在不同水平上的面积、厚度随时间的变化趋势。结果咬肌体积与横截面面积的变化趋势基本相同，体积在术后3、6、12个月时分别缩小至术前的82．02％、77．00％和80．43％，术后各时期体积均明显小于术前（P〈0．05）。A、B、c3个平面咬肌面积的变化：A平面在术后3、6、12个月分别缩小至术前的85．81％、78．86％和81．56％，B平面分别萎缩至术前的80．94％、75．03％和77．04％，而C平面近似原下颌角角区下降最多，分别为13．46％、11．48％和13．89％。各测量数值与术前比较均有显著差异（P〈0．05，P〈0．05，P〈0．01）。咬肌厚度的变化：A平面在术后3、6、12个月时分别缩小16．54％、15．85％、4．69％，术后12个月时与术前比较无明显差异。而B、C平面在各随访时间的厚度与术前比较均有显著差异（P〈0．05）。结论下颌角截骨术使咬肌发生了自行萎缩，原下颌角角区（C平面）的咬肌萎缩最为明显。因此在下颌骨截骨的术前的预测中应考虑到咬肌的萎缩，以更好地指导手术。
Objective To evaluate the morphological change of masseter after the mandibular angle osteotomy. Methods Computerized tomography（CT） examination was performed on 120 patients treated by mandibular angle osteotomy before operation and at 3,6,12months after operation, respectively. The pre- and postoperative masseter muscle thickness and cross-sectional area were evaluated using 3D CT images observed from 3 selected slice planes, which were paralleled with Frankfurt horizontal plane. These CT images were stored and three-dimensional reconstruction were made for calculation of masseter muscle volume through software. Results After operation, the reduction of the masseter muscle volume and cross-sectional area was seen. The volume of the masseter at 3,6,12 months postopertively decreased to 82.02% ,77.00% and 80. 43% （P 〈0. 05）. The cross-sectional area at 3,6,12 months postoperatively decreased to 85.81% ,78.86% and 81.56% at A plane, 80. 94% ,75.03% and 77.04% at B plane,and reached to 13.46% ,11.48% and 13.89% at C plane（P〈0.05, P 〈0.05, P 〈0.01）. The masseter thickness after operation was significantly different from that before operation during the follow-up period, but not at 12 months after operation at A plane. Conclusions The masseter atrophy happens spontaneously after mandibular angle osteotomy, especially at the region of mandibular angle. It should be considered during surgical design.
出处
《中华整形外科杂志》
CAS
CSCD
北大核心
2010年第5期340-344,共5页
Chinese Journal of Plastic Surgery
基金
基金项目：上海高校创新团队发展计划资助
关键词
下颌角截骨术
咬肌
体层摄影术
螺旋计算机
成像
三维
Mandibular angle osteotomy
Masseter muscle
Tomography, spiral computed
Imaging, three-dimensional
