骨性Ⅲ类错(牙合)正颌手术前、后面部软、硬组织变化比率的三维研究

Three dimensional study on change ratios of hard and soft tissue after orthognathic surgery

目的 :研究骨性Ⅲ类错(牙合)畸形患者面部软、硬组织三维方向上变化的相关性,以及手术前、后软、硬组织的变化比率,以期更好地对术后软组织外貌进行预测。方法:对20例骨性Ⅲ类错(牙合)畸形成人患者分别于术前2周及术后3个月进行颅面CT扫描和三维重建及面部软组织3D摄影成像,将采集的数据导入Dolphin软件,转换为三维面像数字化模型,建立三维测量坐标系(轴面、矢状面及冠状面),筛选19个软、硬组织标记点并进行测量、对比和配对,共12对。读取标记点的三维坐标(X、Y、Z),进行手术前、后的定点对比测量,采用SPSS 22.0软件包对测量数据进行统计学分析。结果:12对软、硬组织标志点在X轴即左右方向仅Pn/A、Gn'/Gn及Me'/Me存在相关性,在Y轴即上下方向仅Gn'/Gn存在相关性,在Z轴上所有软、硬组织配对点均存在相关性。除UL'/UI及UL/SPr外,均为高度相关。手术前、后,下颌的软、硬组织测量标志点的变化比率大于上颌。结论:骨性Ⅲ类错(牙合)畸形患者双颌手术前、后软、硬组织的变化主要集中于Z轴即前后向的变化,各软、硬组织配对标志点间呈线性相关关系,且下颌软、硬组织位移比率大于上颌。

PURPOSE:To investigate the change ratios of soft and hard tissue after orthognathic surgery three-dimensionally in osseous ClassⅢpatients,in order to predict postoperative soft tissue three-dimensionally.METHODS:Twenty adult patients were selected as the experimental group,craniofacial spiral CT and three-dimensional(3 D)stereophotogrammetry were conducted 2 weeks before surgery and 3 months after surgery.Dolphin imaging software was used to establish 3 D image digitizing model and 3 D measurement coordinate system.Nineteen soft and hard tissue land marks were selected and matched into 12 pairs.3 D coordinate value of these landmarks were read both before and after surgery and were used for statistical analysis with SPSS 22.0 software package.RESULTS:There was a linear relationship only in Pn/A,Gn’/Gn and Me’/Me in X axis,in Gn’/Gn in Y axis and all pairs of landmarks had a close correlation except UL’/UI and UL/SPr in Z axis.Additionally,the change ratio between soft and hard tissue landmarks of mandible was greater than maxilla.CONCLUSIONS:The changes of soft and hard tissue after orthognathic surgery only lie in Z axis(forward and backward),each pair of matched landmarks exhibits a linear relationship,and the change ratio of mandible is greater than the maxilla.