OBJECTIVE The aim of this study was to explore the cause of type B condylar head fracture after parasymphyseal impact, and evaluate the biomechanics of osteosynthesis using two positional screws for the repair of this type of fractures. METHODS A finite element model of the mandible was created, and a parasymphyseal impact was simulated using Mimics 10.01 and Abaqus 6.10 software. The type B condylar head fracture was simulated in the right condyle using a mimics simulation cut with polyplane module according to the analyzed results together with clinical experience, and the left condyle was used as a control. Two positional screws were used for rigid internal fixation of the fracture. von Mises stress distributions in the condyles and screws were analyzed. RESULTS The von Mises stress generated in parasymphyseal trauma simulation showed a significant concentration in the sagittal direction of the condyle. In two-positional-screw osteosynthesis of the condylar head fractures, stress concentration appeared within the screws in the gap area between the two fractured segments and the area around the screw head. A small amount of stress was distributed in the screw holes and on the posterior surfaces of both segments. The von Mises stress was negligible in the fractured sagittal surfaces. CONCLUSION It is reasonable to attribute the cause of type B condylar head fracture to the anatomical features of the condyle. The biomechanics of two-positional-screw osteosynthesis revealed that the stress can transmit through the screws to the medial fragments, and the stresses on both sagittal fractured surfaces are minimal.

中文翻译：

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使用两个定位螺钉对B型con突头部骨折和骨合成进行有限元分析。

目的本研究的目的是探究副突突撞击后B型con突头部骨折的原因，并使用两个定位螺钉修复这种类型的骨折，评估骨合成的生物力学。方法建立下颌骨的有限元模型，并使用Mimics 10.01和Abaqus 6.10软件模拟副颌骨的撞击。根据分析结果和临床经验，采用带多平面模块的模拟模拟切口在右侧con突中模拟B型con突头部骨折，并以左侧con突为对照。使用两个定位螺钉对骨折进行刚性内固定。分析了Mi和螺钉中的冯·米塞斯应力分布。结果在副突突创伤模拟中产生的冯·米塞斯应力显示showed突矢状方向明显集中。在two突头骨折的两位置螺钉接骨术中，应力集中出现在两个骨折段之间的间隙区域和螺钉头周围区域的螺钉内。少量应力分布在螺丝孔和两个节段的后表面上。在断裂的矢状面中，von Mises应力可忽略不计。结论将B型con突头部骨折的原因归因于the突的解剖特征是合理的。两位置螺钉接骨的生物力学表明，应力可以通过螺钉传递到内侧碎片，