Korioth T W, Hannam A G
Department of Oral Science, Minnesota Dental Research Center for Biomaterials and Biomechanics, School of Dentistry, University of Minnesota, Minneapolis 55455.
J Orofac Pain. 1994 Spring;8(2):178-89.
Differential, functional loading of the mandibular condyles has been suggested by several human morphologic studies and by animal strain experiments. To describe articular loading and the simultaneous forces on the dental arch, static bites on a three-dimensional finite element model of the human mandible were simulated. Five clenching tasks were modeled: in the intercuspal position; during left lateral group effort; during left lateral group effort with balancing contact; during incisal clenching; and during right molar clenching. The model's predictions confirmed that the human mandibular condyles are load-bearing, with greater force magnitudes being transmitted bilaterally during intercuspal and incisal clenching, as well as through the balancing-side articulation during unilateral biting. Differential condylar loading depended on the clenching task. Whereas higher forces were found on the lateral and lateroposterior regions of the condyles during intercuspal clenching, the model predicted higher loads on the medial condylar regions during incisal clenching. The inclusion of a balancing-side occlusal contact seemed to decrease the forces on the balancing-side condyle. Whereas the predicted occlusal reaction forces confirmed the lever action of the mandible, the simulated force gradients along the tooth row suggest a complex bending behavior of the jaw.
多项人体形态学研究和动物应变实验表明，下颌髁突存在差异性的功能负荷。为了描述关节负荷以及牙弓上的同时作用力，对人类下颌骨的三维有限元模型进行了静态咬合模拟。模拟了五种咬合任务：在牙尖交错位；左侧侧方咬合用力时；左侧侧方咬合用力且有平衡接触时；切牙咬合时；以及右侧磨牙咬合时。模型预测结果证实，人类下颌髁突具有承重功能，在牙尖交错位和切牙咬合时，双侧传递的力大小更大，在单侧咬合时，力也通过平衡侧关节传递。髁突的差异性负荷取决于咬合任务。在牙尖交错位咬合时，髁突的外侧和后外侧区域受力更大，而模型预测在切牙咬合时，髁突内侧区域受力更大。包含平衡侧咬合接触似乎会减小平衡侧髁突上的力。虽然预测的咬合反作用力证实了下颌骨的杠杆作用，但沿牙列模拟的力梯度表明下颌骨存在复杂的弯曲行为。
