Study for the effects of different sensory-evaluated food textures on the pattern of masticatory mandibular movements

本研究旨在探讨不同拟声词的食物质感对咀嚼运动的影响，并找出不同食物质感对应的有意义因素。三名健康受试者使用下颌运动跟踪装置在6个自由度下评估咀嚼运动，使用五种不同的测试食物：杏仁、硬米饼和轻米饼作为硬食物，苹果和口香糖作为软食物。分析了切牙尖、工作髁和非工作髁以及整个下颌骨在咬合期的运动情况。咀嚼苹果时，正面切牙的开口路径向工作侧倾斜，其他4种食物的开口路径向非工作侧倾斜。对于较硬的食物，切牙在水平面上从后方和外侧进入尖间位置，当整个下颌骨向后和内侧平移时，工作髁显示前和明显的内侧运动。对于软性食物，切牙的运动与侧缘在水平面上的运动几乎一致，下颌骨围绕工作髁向内旋转。虽然下颌运动的整体路径是单独不同的，但在水平面上最终闭合的下颌运动似乎与食物的质地有关。从下颌运动的角度来看，分析咬合期咀嚼运动在水平面上的变化有助于揭示咬合感觉系统与食物质地的关系。

This study aimed to investigate the effects of different sensory-evaluated food textures with onomatopoetic words on masticatory movements, and to identify meaningful factors that correspond to different food textures. Three healthy subjects were evaluated masticatory movements with a jaw movement tracking device in 6 degrees of freedom using five different test foods: almond, hard and light rice crackers for hard foods, apple and chewing gum for soft foods. The movements of the incisor point, working and non-working condyle and the entire mandible at the occlusal phase were analyzed.When chewing apple, the opening paths of the incisor in the frontal plane turned towards the working side, while the paths of 4 other foods were toward the non-working side. For harder foods, the incisor entered the intercuspal position from a rear and lateral in the horizontal plane, the working condyle showed anterior and noticeable medial movements as entire mandible translated posteriorly and medially. For soft foods, the incisor movements were nearly coincidental with the lateral border movements in the horizontal plane, and the mandible rotated around the working condyle to the inner side. Although the overall paths of the mandibular movements are individually different, it appears that jaw movement at final closure in the horizontal plane is peculiar to the texture of the food.From the standpoint of mandibular movements, it is suggested that analysis of masticatory movements during the occlusal phase in the horizontal plane is useful for revealing the relationship between the occlusal sensory system and food texture.