A physiological method to determine the vertical dimension of occlusion based on accuracy and precision of isometric contraction of masseter muscles

2018 Fiscal Year Final Research Report

• Project/Area Number: 17K17199
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Prosthodontics/ Dental materials science and
• Research Institution: Osaka Dental University
• Principal Investigator: TANAKA Yuto 大阪歯科大学, 歯学部附属病院, 助教 (10711038)
• Research Collaborator: Trulsson Mats カロリンスカ研究所, 教授
• Project Period (FY): 2017-04-01 – 2019-03-31
• Keywords: 咬合高径

Outline of Final Research Achievements

Previous studies focused on the “power element” of jaw closing muscles, when it comes to the vertical dimension of occlusion (VDO), however, the “manipulative element” of the isometric contraction of the muscles has not been considered. We believe that the VDO should be determined by physiological aspects, therefore, we examined the effects of altering VDO in edentulous subjects on accuracy and precision of the isometric contraction of masseter muscles. With an increased VDO, the activity of masseter muscles kept the target force level less precisely and accurately compared to the original VDO. Similarly, with a decreased VDO, the activity of masseter muscles also kept the target force level less precisely and accurately compared to the original VDO. Thus, the edentulous subjects displayed an impairment of the estimation presumably due to the distraction of the sensory information from the muscle spindle of jaw-closing muscle caused by altering the VDO.

Free Research Field

補綴歯科学

Academic Significance and Societal Importance of the Research Achievements

時々刻々と変化する状況の中で的確な機能運動を遂行するためには、従来着目されていた最大力の発揮というよりも、必要な力を的確なタイミングで発揮する能力すなわち巧緻性調節能力に着目することが重要だと考えている。また、臨床的に広く使用されている器具を多く使用するので、安価でありながら安全性が高い。本研究により、運動生理学的根拠に基づき、かつ広く普及できる顎間関係の記録法を提供できる可能性が示唆された。