基于三维CT配准技术的下颌矢状劈开去骨术的临床研究

Clinical research of angle-splitting ostectomy based on three dimensional computed tomography true-up technique

目的探讨下颌矢状劈开去骨术后下颌骨的形态学变化。方法选择2006年1月至2008年4月行下颌矢状劈开去骨术的10例患者为研究对象,完整采集每例患者术前、术后即刻、术后半年的头面部CT数据,应用逆向工程软件Surfacer V9,利用三维CT分体重建和配准分割技术,对下颌矢状劈开去骨术后半年的效果及下颌骨局部骨质的再生情况进行评价。结果1)下颌矢状劈开去骨术后半年,下颌骨局部有明显凹陷,比术前平均凹陷(3.64±1.67)mm,以下颌骨外斜线部位最为明显;术后半年去骨区域体积缩小率为55%±9%。2)与术后即刻相比,术后半年局部骨质有再生,去骨区域有84.6%±7.3%的骨质属新生骨,增生的主要部位为下颌角区。结论行下颌矢状劈开去骨术可达到缩小面下部宽度的目的,术后应尽量减少咬肌活动。

Objective To illustrate the morphological changes of mandible after angle-splitting ostectomy. Methods From January 2006 to April 2008, 10 cases had undergone mandibular angle-splitting ostectomy to reduce the width of the lower face. For each patient, CT datum of mandible at three stages （preoperative, immediate postoperative, 6 months postoperative） were collected. By the application software of reverse engineering （Surfacer V9） and true-up and dissection techniques based on three-dimensional spiral computed tomography （3D-CT）, operative efficacy and bone regeneration at the operation area of angle-splitting ostectomy were evaluated 6 months postoperative. Results 1）Concavity could be seen at the angle-splitting ostectomy area 6 months postoperative, especially at the mandibular external oblique line region. Average cup depth was （3.64±1.67） mm by contrasted to preoperative. Diminution of bone volume was 55%±9% for the local operative area 6 months postoperative. 2）Bone regeneration could be seen at the area that mandibular outer cortex had been removed. Compared with immediate postoperative, ratio of neeformative bone was 84.6% ±7.3% 6 months postoperative. The main region of bone regeneration was mandibular angle. Conclusion Mandibular angle-splitting ostectomy is an effective technique for reducing the width of the lower face. Masseter muscular movement should be restricted postoperative to prevent hyperostosis at the angle area.