The development of the optimum occlusal morphology occlusal facets in harmony with jaw movement and the clinical application

本研究的目的是从与颌骨运动协调的角度来确定咬合面的最佳形态。研究结果如下：1.MIMA提出的咬合参考面不仅适用于单路径下颌运动，也适用于多路径下颌运动。利用侧向、后退和前伸滑动运动的轨迹定义了四种类型的咬合参考面。在咀嚼周期的第四和第五阶段，与这些咬合参考面和谐的咬合面对下颌运动没有明显的干扰。我们提出用倾角和与方位角对应的M(D)值来定量评价咬合小关节。这种评估方法在比较受试者的咬合参考面和咬合面时具有重要意义。用颌骨跟踪仪(MM-JI)测量实验用M型和D型侧牙导向器对尖牙的侧向偏移量。D型侧牙引导比M型侧牙引导更多地引导工作髁点的后路路径。提示D型导引可能导致颞颌关节负荷过重。

The purpose of this study was to determine the optimum morphology of occlusal facets from the view point of harmony with jaw movements. Results were as follows.1. Occlusal reference surfaces, proposed by Mima, were applicable not only single path but also multiple pathes of jaw movements.2. Four types of occlusal reference surfaces were defined by using the trajectories of lateral, retrusive and protrusive sliding movements. The harmonious occlusal facets with these occlusal reference surfaces produced no considerable interference with jaw movement during the forth and fifth phases of the chewing cycle.3. We proposed to evaluate occlusal facets quantitatively by using inclination angle and M (D) value corresponding with azimuth angle. This evaluating method was significant in comparison of occlusal reference surfaces to occlusal facets of subjects.4. Lateral excurisions were measured by using a jaw tracking device (MM-JI) with experimental M type and D type lateral tooth guidances on canine teeth. D type lateral tooth guidance led more posterior path way of working condylar point than M type lateral tooth guidance. This suggested that D type guidance may cause overload in temporomandibular joint.