Mizuno T
Nihon Hotetsu Shika Gakkai Zasshi. 1989 Apr;33(2):303-12. doi: 10.2186/jjps.33.303.
The purpose of this study is to clarify the relationship between the occlusal form of a molar and mandibular movement. For this purpose I measured the occlusal form of the upper first molar, and the 3-dimensional movement of the lower first molar during the grinding movement in chewing-similar to empty jaw movement. In this study the following three parameters were analyzed.; (1) the distance between the upper and lower first molars in the lateral occlusal position, (2) the inclination of the cusp-slope, (3) the inclination of the lower first molar path. Results were follows: 1) On the working side, the inclination of the cusp-slope is closely connected to that of the path, 2) On the non-working side, the correlation between the inclination of the cusp-slope, and that of the path was so weak, as to be statistically insignificant. 3) The distance between the molars tended to increase as the inclination of the path steepened. This tendency was marked on the non-working side. The results mentioned above proved that, in cases with steeper anterior guidance, the upper and lower first molars disclude more on both the working and non-working sides. On the working side, however, the steeper cusp-slope prevents excessive disclusion of molars.
本研究的目的是阐明磨牙的咬合形式与下颌运动之间的关系。为此，我测量了上颌第一磨牙的咬合形式，以及在类似于空口运动的咀嚼磨耗运动过程中下颌第一磨牙的三维运动。在本研究中，分析了以下三个参数：（1）侧方咬合位时上下第一磨牙之间的距离；（2）牙尖斜面的倾斜度；（3）下颌第一磨牙运动轨迹的倾斜度。结果如下：1）在工作侧，牙尖斜面的倾斜度与运动轨迹的倾斜度密切相关；2）在非工作侧，牙尖斜面的倾斜度与运动轨迹的倾斜度之间的相关性较弱，在统计学上无显著意义；3）随着运动轨迹倾斜度的增加，磨牙之间的距离趋于增大。这种趋势在非工作侧更为明显。上述结果证明，在前伸引导较陡的情况下，上下第一磨牙在工作侧和非工作侧的脱离接触更多。然而，在工作侧，较陡的牙尖斜面可防止磨牙过度脱离接触。
