间接性TMJ损伤的生物力学初步研究

An Elementary Study of Biomechanics on the Indirect Trauma of TMJ.

目的 :研究间接性TMJ损伤时下颌骨不同部位在致伤过程中的生物力学改变情况。方法 :采用颏部撞击法对 6个新鲜羊头颅以 4kg和 10kg的压力推动 0 .84 5kg的圆柱形钢质抛射体进行撞击 ,对头颅加速度、双侧下颌骨体部、髁突颈部以及颞骨部的应变变化情况进行检测 ,应用新研制的生物撞击系统数据采集与分析软件对采集到的信号进行分析。结果 :随撞击速度的增加 ,头颅加速度和各检测部位的应变也随之加大 ,髁突颈部可产生最大应变 ,颞骨部应变明显减小 ,说明颞颌关节的存在可减小颏部撞击伤对颅脑的损伤。在外力作用于颏部时 ,髁突颈部受到的应力最大 ,因而较其他部位容易发生骨折。当髁突颈部所受应力超出其自身生理范围时 ,即发生髁突骨折。结论 :撞击速度和下颌骨内应力的变化是衡量下颌部损伤 。

Objective: To investigate the biomechanics charge of varieus sites of mandible after indirect TMJ ingury. Methods: The cyclindered-projectile weighed 0.845 kg was pushed under the pressure of 4 kg and 6 kg, and was impacted at the chin of 6 fresh goat head in this experiment. The head acceleration and the strain of both sides of the mandible and neck of the condyle as well as the temporal bone were monitered. A new designed software was applied in analyzing the results. Results: The strain of the condylar neck was much more than other parts, and the TMJ may reduce the injury of the brain. The strain and the head acceleration got higher with the improvement of the speed of the projectile. Conclusion: The impact velocity and the change of strain in the mandible during the impact are important biomechanical parameters influencing the injury severity of TMJ.