摘要目的:参考不同平面在偏突颌畸形伴高低眼患者手术模拟设计的对称性差异。方法:2019年1月至2020年6月，天津市口腔医院正颌外科偏突颌畸形患者15例，男3例、女12例，年龄18~26岁，平均23.8岁。分别建立3种不同三维参考平面系统；选取软硬组织解剖标志点并测量各标志点距离正中矢状面的距离，用镜像技术定性分析颅骨对称性。通过单因素方差分析评估3种参考平面在偏突颌伴高低眼患者手术模拟对称性的差异。结果:定性分析：通过镜像技术可见，在3种测量平面中用方法3参考平面进行手术模拟的骨组织对称性最佳，方法2与方法1对称性较差。定量分析：头颅硬组织测量指标中用方法3建立的参考平面各标志点距离正中矢状面的距离(1.65±1.19) mm与方法1、方法2之间差异有统计学意义[(3.37±1.58)、(3.26±2.36) mm， P<0.05])；方法1、方法2之间差异无统计学意义( P>0.05)。软组织测量结果与硬组织保持一致，同时各软组织标志点在方法3距离正中矢状面距离非常小，平均误差<0.5 mm，与临床面诊结果一致。 结论:数字化模型外科技术可辅助正颌外科进行手术方案设计与预测分析，尤其在特殊偏突颌畸形患者设计中有重要作用。

abstractsObjective:To analyze the symmetry of different reference planes in the surgical simulation design of patients with protrusive jaw deformity with high and low eyes.Methods:Fifteen patients with partial jaw deformity were selected from January 2019 to June 2020, including 3 males and 12 females, aged 18-26 years, with average 23.78 years. Inclusion criteria were that the patients, aged more than 18 years, were diagnosed as protrusive jaw deformity with maxillary occlusal plane tilt and high and low eyes by clinical and imaging analysis. Three different 3D reference plane systems were established by different modeling methods. The distance between the landmarks of soft and hard tissues and the median sagittal plane was measured. The symmetry of skull was qualitatively analyzed by mirror image technique. The difference of three reference planes in surgical simulation symmetry of patients with protrusion jaw and high and low eyes was evaluated by one-way ANOVA.Results:Qualitative analysis showed that in the three measurement planes, the symmetry of the third reference plane was the best, and the symmetry of the second and the first was poor. Quantitative analysis showed that in measurement index of hard tissue, there was statistical difference between the distance of each landmark in the reference plane established by Method 3 and Method 1, Method 2 [(1.65±1.19) mm; (3.37±1.58) mm; (3.26±2.36) mm, P<0.05], but there was no statistical difference between Method 1 and Method 2 (P > 0.05). The measurement result of soft tissue was consistent with that of hard tissue, and the distance of each landmark in Method 3 from the median sagittal plane was very small, and the mean error was less than 0.5 mm, which was consistent with the clinical results. Conclusions:Digital model surgery technology can assist orthognathic surgeons in the design and prediction of surgical scheme, especially for patients with special partial jaw deformity.