Wang Xiaoxu, Xue Jiaojiao, Wang Xiaoting, Fan Mingyue
Laboratory of Dental Biomaterials and Tissue Regeneration, Shanghai Xuhui District Stomatological Hospital, Shanghai, China.
Front Bioeng Biotechnol. 2025 Jul 3;13:1625027. doi: 10.3389/fbioe.2025.1625027. eCollection 2025.
This study investigates the biomechanical effects of different orthodontic movement patterns on the alveolar bone in the adjacent edentulous region through finite element analysis (FEA) of maxillary central incisor displacement mechanisms.
A three-dimensional FEA model was constructed comprising the maxilla, upper dentition (with exclusion of the right maxillary central incisor), periodontal ligament (PDL), fixed orthodontic appliance bracket, and archwire system. The initial displacement characteristics and stress distribution patterns of the maxillary left central incisor (tooth 21) and the surrounding alveolar bone were quantitatively analyzed using ANSYS software.
Under an intrusion force approximately four times the lingual reactionary force, the maxillary central incisor underwent pure axial intrusion without labial or lingual tipping. Adjacent tooth movement had minimal mechanical impact on the edentulous alveolar bone (<0.5% strain). The resistance center of the incisor was identified 0.43 times the root length apical to the alveolar ridge crest, necessitating precise force vector alignment to achieve bodily movement without rotational displacement or alveolar bone remodeling. For incisal tipping correction, a horizontal tensile force (F) combined with an archwire-bracket-induced moment (M) allows controlled tipping via modulation of the M/F ratio. However, excessive force risks pathological root resorption and alveolar bone atrophy in edentulous regions.
Bodily movement of the central incisor, when guided through the resistance center, does not significantly remodel the edentulous alveolar bone. Moreover, effective tipping correction requires precise M/F ratio control to optimize movement efficiency while minimizing iatrogenic risks. Deviations from optimal force parameters substantially increase the likelihood of alveolar bone atrophy.
本研究通过对上颌中切牙位移机制的有限元分析（FEA），探讨不同正畸移动模式对相邻无牙区牙槽骨的生物力学影响。
构建一个三维有限元分析模型，包括上颌骨、上牙列（不包括右上颌中切牙）、牙周膜（PDL）、固定正畸矫治器托槽和弓丝系统。使用ANSYS软件对上颌左中切牙（21号牙）及其周围牙槽骨的初始位移特征和应力分布模式进行定量分析。
在上颌中切牙受到约为舌侧反作用力四倍的压低力时，该牙进行了单纯的轴向压低，无唇向或舌向倾斜。相邻牙的移动对无牙牙槽骨的力学影响极小（应变<0.5%）。切牙的阻力中心位于牙槽嵴顶根尖方向牙根长度的0.43倍处，因此需要精确对齐力向量，以实现整体移动而无旋转位移或牙槽骨重塑。对于切牙倾斜矫正，水平拉力（F）与弓丝 - 托槽诱导的力矩（M）相结合，可通过调节M/F比值实现可控倾斜。然而，过大的力有导致无牙区病理性牙根吸收和牙槽骨萎缩的风险。
当通过阻力中心引导时，中切牙的整体移动不会显著重塑无牙牙槽骨。此外，有效的倾斜矫正需要精确控制M/F比值，以优化移动效率并最小化医源性风险。偏离最佳力参数会大幅增加牙槽骨萎缩的可能性。
