咀嚼肌牵动的下颌骨三维有限元建模与数值分析

目的：应用有限元方法分析咀嚼肌牵动的下颌骨应力状态。方法：采用数字中国人下颌骨CT图像三维重建，生成有限元模型，通过解剖学研究和测量，确立颞肌、咬肌、翼内肌、翼外肌的附着部位面积和肌力线方向。结果：建立了咀嚼肌牵动的下颌骨生物力学分析模式，有限元计算得到下颌骨应力分布状态，Von Mises应力主要集中于髁突，冠突，咀嚼肌附着部位和磨牙区，当右侧第1磨牙与第2磨牙咀嚼模拟时应力峰值为20．61MPa．当第1前磨牙与第2前磨牙咀嚼模拟时应力峰值达到了22．09MPa。结论：有限元分析技术，结合下颌骨血管神经走向及He力与咀嚼功能测定等，为下颌骨截骨术和骨牵张术提供了一种术前设计的定量方法。

Three-dimensional finite element modeling and numerical analysis of mandible pulled by masticatory muscles

To analyse stress state of mandible pulled by masticatory muscles. Methods: The finite element model of mandible was reconstructed by CT scans of "digital Chinese human", and attachment area and force direction of masticatory muscles, including temporal muscle, masseter muscle, medial pterygoid muscle, lateral pterygoid muscle, were measured based on anatomic investgation. Results: Biomechanical analysis model of mandible pulled by masticatory muscles was created. The stress distribution of mandible was calculated by finite element method, which showed that Von Mises stresses were concentrated on condylar process, coronoid process, attachment spot of masticatory muscles, and molar area. The peak value of Von Mises stress was 20.61 MPa in view of first molar and second molar chewing simulation, as was 22.09 MPa in view of first premolar and second premolar chewing simulation. Conclusions: Finite element analysis technology, combining with measurements of occlusal force and nerve vesset position, can provide a qnantificational method for preoperative design of osteotomy and bone stretching technique.