下颌角弧形截骨线的设计与临床意义

目的：为下颌角截骨术设计安全、美观的弧形截骨线。方法将150例（300侧）成人离体下颌骨的下颌管暴露。观测下颌管的走行特点；测量下颌管关键点距下颌缘的距离；观测下颌孔与下牙槽弓的位置关系；依据观测结果设计出符合个性化需求的弧形截骨线。结果下颌管关键点A1、B1、C1、D1、E1距下颌缘的距离分别为（14．02±2．23）mm、（21．06±3．90）mm、（14．08±3．68）mm、（13．60±2．80）mm、（14．55 ± 3．34）mm ，各点的最大截骨宽度分别为（10．05 ± 4．00）mm、（15．06±2．88）mm、（8．08±3．88）mm、（6．09 ± 3．45）mm、（7．06±3．56）mm ；下颌孔与下牙槽弓位于同一平面的概率为96％；截骨线的后端A点不应高于下颌孔平面，3条截骨线的前端C点、D点、E点分别是经下颌支前缘、下颌牙M 2位、下颌牙P4位向下所引垂线与下颌缘的交点。结论下颌角弧形截骨线的设计适应个性化需求，符合解剖学特征和美学要求，具有标志明确、易于操作、安全性高、术后效果好的优点。

Clinical significance and design of the curved osteotomy line on mandibular angle

Objective To design safe and beautiful curved osteotomy line for mandibular angle osteotomy .Methods Expo‐sing 150 cases(300 sides) of mandible tube in the mandible bone of adults;Observing the characteristics of the movement of man‐dibular canal;measuring the distance from the critical dot of mandibular canal to marginal mandibular ;observing the positional rela‐tionship between mandibular foramen and the inferior alveolar arch;designing the curved osteotomy line based on observations to meet the individual needs .Results T he distance betw een the key points of mandibular canal A1 ,B1 ,C1 ,and D1 ,E1 and the mandib‐ular edge come as (14 .02 ± 2 .23)mm ,(21 .06 ± 3 .90)mm ,(14 .08 ± 3 .68)mm ,(13 .60 ± 2 .80)mm ,(14 .55 ± 3 .34)mm ,respective‐ly ;the maximum width each were (10 .05 ± 4 .00)mm ,(15 .06 ± 2 .88)mm ,(8 .08 ± 3 .88)mm ,(6 .09 ± 3 .45)mm ,(7 .06 ± 3 .56) mm ;the probability that mandibular foramen and inferior alveolar of the bow was located in the same plane falls on 96% ;the rear end of the point A of the osteotomy line should not be higher than the plane of the lower jaw holes ,the front point of three osteoto‐my line C ,D ,E ,fall respectively on the point intersection where the vertical line led downward via the edge of the ramus ,the man‐dibular teeth M2 ,P4 met the marginal mandibular .Conclusion The design of curved osteotomy line for mandibular angle osteotomy meets the individual needs ,in line with the anatomical features and aesthetic requirements which takes the advantages as easy‐opera‐tion with clear signs ,high security and preferable effect after operation .