颞下颌关节-下颌骨-Herbst矫治器系统三维有限元模型的建立

Establishment of the Three Dimensional Finite Eliment Model of Temporomandibular Joint-Mandible-Herbst Appliance System.

目的 建立“颞下颌关节 -下颌骨 -Herbst矫治器系统”的三维有限元模型 ,为模拟Herbst矫治器工作状态 ,进一步探讨Herbst矫治器矫治机理奠定基础。方法 采用CT扫描技术 ,以处于青春生长高峰期、Ⅱ类骨性错牙合的儿童的颅面骨作标本 ,以及使用图形数字化仪等方法 ,建立包括完整天然牙列和颞颌关节的下颌骨三维正交各向异性有限元模型 ,在此模型上增加Herbst矫治器 ,模拟临床上Herbst矫治器的工作状态。结果 建立了“颞下颌关节 -下颌骨 -Herbst矫治器系统”的三维正交各向异性有限元模型 ,提高了模型的相似性 ,确保实验结果的准确性。结论 该模型有较好的生物力学相似性和几何相似性 ,为研究Herbst矫治器的矫治机理 ,提供了有利的条件 ,使实验结果更真实、可靠。

Objective To set up the model of Temporomandibular joint-mandible-Herbst appliance system so as to study the mechanism of Herbst appliance. Methods Computer Tomography (CT) technique and image digitizing method were used to reconstuct the craniofacial skelton of child with skeletal class Ⅱ malocclusion who is in the puberty growth spurt. The 3-DFEM of mandible including TMJ and the whole teeth was established, and Herbst appliance covered the modal, so the working state of Herbst appliance was imitated. Results The 'Temporomandibular joint-mandible-Herbst appliance system' was set up. Conclusion The model had a good similartity in biomechanics and geometry. It provided favourable conditions for understanding the working principle of Herbst appliance, and made experimental evidence true.