Orthodontic tooth movement in the alveolar bone is due to the mechanical response of periodontal ligament to applied forces. Definition of a proper constitutive model of the periodontal ligament to investigate its response to orthodontic loading is required. For this purpose, a three-dimensional finite element model of incisor tooth, periodontal ligament, and bone was built utilizing the hydro-mechanical coupling theory. Tooth displacement in response to orthodontic loading was then investigated, and the effect of different mechanical behaviors assigned to the solid phase of the periodontal ligament was compared. Results showed that where the periodontal ligament was placed in tension, pore volume was filled with fluid intake from the bone, but fluid flow direction was from the periodontal ligament toward the bone where the periodontal ligament was placed in compression. Because of the existence of interaction between solid and fluid phases of the periodontal ligament, considering biphasic material formulation was capable to address its microscopic behavior as well as time-dependent and large deformation behaviors. This article provides beneficial biomechanical data for future dental studies in determination of optimal orthodontic force.

中文翻译：

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牙周膜液力耦合的数值模拟。

牙槽骨中的牙齿正畸运动是由于牙周膜对施加力的机械反应所致。需要定义一个适当的牙周膜本构模型以研究其对正畸负荷的反应。为此，利用水力耦合理论建立了切牙，牙周膜和骨骼的三维有限元模型。然后研究了响应正畸负荷的牙齿位移，并比较了分配给牙周膜固相的不同机械行为的影响。结果表明，当牙周膜处于张力状态时，孔体积充满了从骨骼中吸收的液体，但是流体的流动方向是从牙周膜向压迫牙周膜的骨骼。由于牙周膜的固相和液相之间存在相互作用，因此考虑双相材料配方能够解决其微观行为以及与时间有关的大变形行为。本文为确定最佳正畸力提供了有益的生物力学数据，以供将来的牙科研究。