Martinez Choy S E, Lenz J, Schweizerhof K, Schmitter M, Schindler H J
Research Group Biomechanics, Institute for Mechanics, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany.
Department of Prosthodontics, Dental School, University of Würzburg, Würzburg, Germany.
J Oral Rehabil. 2017 May;44(5):375-384. doi: 10.1111/joor.12501. Epub 2017 Mar 28.
Although knowledge of short-range kinetic interactions between antagonistic teeth during mastication is of essential importance for ensuring interference-free fixed dental reconstructions, little information is available. In this study, the forces on and displacements of the teeth during kinetic molar biting simulating the power stroke of a chewing cycle were investigated by use of a finite-element model that included all the essential components of the human masticatory system, including an elastic food bolus. We hypothesised that the model can approximate the loading characteristics of the dentition found in previous experimental studies. The simulation was a transient analysis, that is, it considered the dynamic behaviour of the jaw. In particular, the reaction forces on the teeth and joints arose from contact, rather than nodal forces or constraints. To compute displacements of the teeth, the periodontal ligament (PDL) was modelled by use of an Ogden material model calibrated on the basis of results obtained in previous experiments. During the initial holding phase of the power stroke, bite forces were aligned with the roots of the molars until substantial deformation of the bolus occurred. The forces tilted the molars in the bucco-lingual and mesio-distal directions, but as the intrusive force increased the teeth returned to their initial configuration. The Ogden material model used for the PDL enabled accurate prediction of the displacements observed in experimental tests. In conclusion, the comprehensive kinetic finite element model reproduced the kinematic and loading characteristics of previous experimental investigations.
尽管了解咀嚼过程中拮抗牙之间的短程动力学相互作用对于确保无干扰的固定牙齿修复至关重要，但相关信息却很少。在本研究中，通过使用包含人类咀嚼系统所有基本组成部分（包括弹性食团）的有限元模型，研究了模拟咀嚼周期动力冲程的磨牙咬合过程中牙齿上的力和位移。我们假设该模型可以近似先前实验研究中发现的牙列加载特征。该模拟是一种瞬态分析，即它考虑了颌骨的动态行为。特别是，牙齿和关节上的反作用力源于接触，而非节点力或约束。为了计算牙齿的位移，牙周韧带（PDL）采用基于先前实验结果校准的奥格登材料模型进行建模。在动力冲程的初始保持阶段，咬合力与磨牙的牙根对齐，直到食团发生实质性变形。这些力使磨牙在颊舌向和近远中向倾斜，但随着侵入力增加，牙齿恢复到其初始构型。用于PDL的奥格登材料模型能够准确预测实验测试中观察到的位移。总之，综合动力学有限元模型再现了先前实验研究的运动学和加载特征。
