野生双峰驼下颌骨的三维重建与应力分析

通过对5个野双峰驼(Camelus bactrianus ferus)下颌骨进行螺旋CT扫描,利用软件Amira 3.1.1对CT扫描图三维重建得到下颌骨三维点云图,并利用Geomagic软件进行实体化,通过有限元分析软件Ansys 14.0对野双峰驼下颌骨角部施加1000 N大小的力后对下颌骨进行有限元分析,得到下颌骨在受力时的应力分布情况:当左下颌角受到水平向右垂直于矢状面的外力时,左下颌角及髁状突颈部极易造成骨折,左颏孔区可能会出现骨裂,而其余部分仅会造成轻微损伤。当右下颌角下缘受到垂直向上垂直于矢状面的外力时,也易出现同样的结果。由此得出结论:当野双峰驼下颌骨角部受到瞬间外力时,应力主要集中在施加力所在骨支的薄弱区域,应力较大部位与骨折易发部位密切相关;且在薄弱区域,下颌角及髁状突颈部的损害最为严重。以上结果有利于深入了解野双峰驼下颌骨应力分布情况,并为骨三维重建在生物学领域的应用提供理论依据。

Three-Dimensional Reconstruction and Stress Analysis of the Mandible of Wild Bactrian Camel

We scanned five wild camel mandibles using spiral CT and acquired a 3D point cloud of the mandible by the three-dimensional reconstruction of the mandible using software Amira 3.1.1.We constructed a solid model using Geomagic software.We conducted the finite element analysis by applying a force of 1,000 N on the mandibular angle using software Ansys 14.0.When external rightward horizontal force was applied perpendicular to the sagittal plane of left mandibular angle,the side of the mandibular angle and the condylar neck were easily fractured.In addition,the left mental foramen showed hairline fracture,and the remaining mandible was slightly damaged.When upward force was applied perpendicular to the sagittal plane on the inferior border of the right mandibular angle,the result was the same as above.While instantaneous forces were applied on the mandibular angle,Von Mises stress mainly concentrated on the weak parts of the mandible.The location where stress was strong was closely related to the position most susceptible to fracture.The mandibular angle and condylar neck were severely damaged at this weak position.These results might guide further investigation of stress distribution on the mandible of wild bactrian camel and provide a basis for three-dimensional reconstruction applications.