本研究首次建立了包括牙髓、牙、牙周腆、硬骨板、松质骨和外层皮质骨的右下颌第一磨牙三维有限元模型,分析其在正畸矫治力作用下的初始应力分布。结果表明:牙齿不同结构的力学性能在应力分布中有重要意义;无论施力点在磨牙颊面还是舌面,应力分布规律类似;力的方向与最大拉、压应力分布区域密切相关。 In this study, a three-dimensional finite element model of the first mandibular first molar including dental pulp, teeth, periodontal ligament, plaque, cancellous bone and outer cortical bone was established for the first time. The initial stress distribution under orthodontic force . The results show that the mechanical properties of different structures of tooth are important in the distribution of stress. The stress distribution is similar regardless of applied force on the buccal or lingual surface of molars. The direction of force is closely related to the distribution area of ​​maximum tensile and compressive stress.