Chen Chia-Chun, Trang Tran-Thi-Ngoc, Wang Ding-Han, Tsou Nien-Ti
Comput Struct Biotechnol J. 2025 Jul 3;27:2946-2954. doi: 10.1016/j.csbj.2025.07.002. eCollection 2025.
Mandible bone is one of the most important parts, as it has a complex structure of trabecular bone and its motion involves both hinge and sliding caused by multiple surrounding muscle loads. However, the numerical models reported in the literature typically adopt uniform bone properties and oversimplify loading conditions. In this study, a finite element model of a rat's mandible was built based on micro-CT images at three different resolutions (20 um, 40 um, and 80 um). The material properties of each element in the model, such as density and Young's modulus, were mapped and assigned based on the brightness of the micro-CT images in the corresponding position, revealing the detailed trabecular bone structure in the model. In addition, eight loads corresponding to the surrounding muscles were applied as boundary conditions to simulate the chewing condition of the rat according to anatomy and experiments. The stress distribution of the mandible and temporomandibular joint can then be determined, having a very good agreement with that observed in the change in bone morphology. The numerical results calculated by the models generated from the micro-CT images of three different resolutions were also analyzed, suggesting the most suitable image resolution for the rat's mandible. The current work provided a novel workflow to generate a more bio-realistic numerical model with high validity.
下颌骨是最重要的部位之一，因为它具有复杂的小梁骨结构，其运动涉及由周围多种肌肉负荷引起的铰链运动和滑动运动。然而，文献中报道的数值模型通常采用均匀的骨特性，并过度简化加载条件。在本研究中，基于三种不同分辨率（20微米、40微米和80微米）的显微CT图像构建了大鼠下颌骨的有限元模型。模型中每个单元的材料特性，如密度和杨氏模量，根据相应位置的显微CT图像亮度进行映射和赋值，从而揭示模型中详细的小梁骨结构。此外，根据解剖学和实验，将对应于周围肌肉的八种负荷作为边界条件施加，以模拟大鼠的咀嚼情况。然后可以确定下颌骨和颞下颌关节的应力分布，这与在骨形态变化中观察到的情况非常吻合。还分析了由三种不同分辨率的显微CT图像生成的模型计算出的数值结果，从而得出大鼠下颌骨最合适的图像分辨率。目前的工作提供了一种新颖的工作流程，以生成一个具有高有效性的更具生物真实性的数值模型。
