van Eijden T M
Department of Functional Anatomy, University of Amsterdam, The Netherlands.
Arch Oral Biol. 1991;36(7):535-9. doi: 10.1016/0003-9969(91)90148-n.
The effect of the three-dimensional orientation of occlusal force on maximal bite-force magnitude was examined in seven human subjects at three different unilateral anteroposterior bite positions (canine, second premolar and second molar). At each position, bite-force magnitude was registered in 17 precisely defined directions using a three-component force transducer and a feedback method. In addition, to assess the efficiency of transfer of muscle to bite force, for bites produced in the sagittal plane, moment-arm length was determined and the produced bite-force moment calculated. The results showed that the largest possible bite force was not always produced in a direction perpendicular to the occlusal plane. Generally, maximal bite force in medial and posterior directions was larger than that in, respectively, corresponding lateral and anterior directions. In each direction the produced force was larger at the posterior bite point than at the anterior bite point. The combined moment produced by the jaw muscles was largest for vertical bites, smallest for posteriorly directed bites and intermediate for anteriorly directed bites. In the case of vertically and anteriorly directed bites the produced moment did not vary significantly with the bite position. Hence, for these bite positions the jaw closing moment of the muscles must have kept constant. In the case of posteriorly directed bites the produced moment decreased when bite position changed from the anterior to the posterior side of the dentition. This indicated that jaw muscle activity had declined.
在七名人类受试者中，于三个不同的单侧前后咬合位置（尖牙、第二前磨牙和第二磨牙）检查了咬合力的三维方向对最大咬力大小的影响。在每个位置，使用三分量力传感器和反馈方法，在17个精确定义的方向上记录咬力大小。此外，为了评估肌肉到咬力的传递效率，对于在矢状面产生的咬合，确定力臂长度并计算产生的咬力力矩。结果表明，最大可能咬力并不总是在垂直于咬合平面的方向上产生。一般来说，内侧和后方方向的最大咬力分别大于相应的外侧和前方方向的最大咬力。在每个方向上，后咬合点产生的力大于前咬合点产生的力。垂直咬合时，颌骨肌肉产生的合力矩最大，向后咬合时最小，向前咬合时居中。对于垂直和向前咬合，产生的力矩随咬合位置变化不显著。因此，对于这些咬合位置，肌肉的颌骨闭合力矩一定保持恒定。对于向后咬合，当咬合位置从牙列的前部变为后部时，产生的力矩减小。这表明颌骨肌肉活动有所下降。
