Saito Yoshio
Orthodontic Science, Department of Orofacial Development and Function, Division of Oral Health Sciences, Graduate School, Tokyo Medical and Dental University.
Kokubyo Gakkai Zasshi. 2006 Mar;73(1):107-15. doi: 10.5357/koubyou.73.107.
The purpose of this study was to clarify the relationship between occlusal condition and changes of bolus property during mastication. The methods and results were as follows. Subjects were selected according to the classification of anterior-posterior occlusal condition of the first molars (Angle' Class I, II, III group). 1. Evaluation of the relationship between occlusal condition and subjective chewing difficulty based on a questionnaire survey using a visual analog scale (VAS): Class II and Class III groups showed significantly higher subjective chewing difficulty compared to the Class I group. 2. Evaluation of the relationship between occlusal condition and changes of bolus property (chewiness) during mastication: In the Class II and Class III groups, the decrease in chewiness during the initial phase of mastication was significantly low compared to that in the Class I group. 3. To verify the results of 2, we examined bolus destruction for different loading directions using FEM and evaluated the differences among the three groups. We also investigated the correlation of the actual jaw movement and the masticatory efficiency according to the loading direction in the three groups: In the Class II and III groups, actual jaw movement was not significantly correlated with the most efficient loading direction in bolus destruction compared to that in the Class I group. These results indicate the correlation between occlusal condition and changes of bolus property during mastication. The subjective chewing difficulty may be one mediating factor. The efficiency of bolus destruction during mastication may also be associated with the relationship between occlusal condition and bolus property.
本研究的目的是阐明咬合状况与咀嚼过程中食团性质变化之间的关系。方法和结果如下。根据第一磨牙前后咬合状况分类（安氏I类、II类、III类组）选择受试者。1. 使用视觉模拟量表（VAS）通过问卷调查评估咬合状况与主观咀嚼困难之间的关系：与I类组相比，II类和III类组的主观咀嚼困难显著更高。2. 评估咬合状况与咀嚼过程中食团性质（咀嚼性）变化之间的关系：在II类和III类组中，咀嚼初始阶段咀嚼性的降低与I类组相比显著较低。3. 为验证2的结果，我们使用有限元法（FEM）检查了不同加载方向下的食团破碎情况，并评估了三组之间的差异。我们还研究了三组中根据加载方向实际下颌运动与咀嚼效率的相关性：与I类组相比，II类和III类组中，实际下颌运动与食团破碎中最有效加载方向的相关性不显著。这些结果表明了咬合状况与咀嚼过程中食团性质变化之间的相关性。主观咀嚼困难可能是一个中介因素。咀嚼过程中食团破碎的效率也可能与咬合状况和食团性质之间的关系有关。
