人下颌骨颏部正中位置枪弹伤的有限元动态模拟及分析

Dynamic simulation and finite element analysis of gunshot wounds to the center of mandible mental region in human

目的采用有限元方法建立颌面部枪弹伤模型,并对人下颌骨颏部正中位置枪弹伤的致伤过程及损伤程度进行动态模拟和分析,探讨建立人下颌骨枪弹伤模型的新方法。方法在以往动物实验建模方法及内置参数的基础上,利用数字化人下颌骨的CT扫描数据建立人下颌骨的三维有限元模型;动态模拟不同投射条件下下颌骨颏部正中位置枪弹伤的发生过程;计算不同投射物以不同初速度及不同角度入射后的终末速度及其穿出下颌骨后的能量损耗数值及能量损耗率;并对所得数据进行比较分析。结果成功模拟了2种投射物以3种初速度及3种入射角度击伤人下颌骨颏部正中位置的动态过程及下颌骨受损伤后各部位的应力分布情况。对模拟数据进行计算后分析发现,致伤条件不同,下颌骨受损伤的严重程度及投射物的致伤效率也不同。结论运用有限元的方法可动态模拟人下颌骨颏部正中位置枪弹伤的致伤过程,并对相关数据进行比较分析,以研究不同致伤条件下下颌骨受损伤的严重程度及投射物的致伤效率。

Objective To establish a finite element model of gunshot wound on the maxillofacial region in human,and to conduct dynamic simulation and analysis of the injury process and degree of gunshot wounds to the center of mandible mental region,so as to explore a new method for establishing a gunshot wound model of human mandible.Methods Based on the existing modeling method and internal parameters,digital CT scan data of human mandible were used to establish a three-dimensional finite element model of human mandible,which was used to dynamically simulate the process of gunshot wounds to the center of mandible mental region under different shot conditions.The residual velocities of the shootings with different projectiles at different entry angles and different impact velocities were calculated;the energy loss of the projectile and the rate of energy loss after exiting the mandible were also calculated;and the obtained data were compared and analyzed.Results The dynamic processes of gunshot wounds to the center of mandible mental region with two projectiles,three impact velocities,and three entry angles were successfully simulated.Meanwhile,the simulation was also done for the stress distribution in different parts of mandible after injury.Computation and the analysis of the modeling data showed that the severity of injuries and the injury efficiency of projectiles differed with different injury conditions.Conclusion Finite element model can dynamically simulate the injury process of gunshot wounds to the center of mandible mental region.It is found that the injury severity on mandible and the injury efficiency vary under different injury conditions.The finite element model is a potentially ideal model for studying the maxillofacial gunshot wounds.