Does the change in masticatory environment in the growing period cause osteoarthrosis of TMJ?

2015 Fiscal Year Final Research Report

• Project/Area Number: 25862026
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Orthodontics/Pediatric dentistry
• Research Institution: Yokohama City University
• Principal Investigator: FUJITA Koichi 横浜市立大学, 附属市民総合医療センター, 助教 (30451909)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 変形性顎関節症 / 咀嚼環境変化 / 顎関節機械受容器 / 成長期

Outline of Final Research Achievements

The present study was conducted to reveal the effects of changes in the orofacial environment (e.g., liquid diet, increased occlusal vertical dimension (iOVD), and nasal obstruction) on the orofacial sensorimotor system (e.g., temporomandibular joint (TMJ) mechanoreceptors, jaw-opening reflex (JOR) and face primary motor cortex (face-M1)) in rats. Alterations in mastication due to liquid diet significantly increased the TMJ mechanoreceptor sensitivity. It was clarified that the adaptation of the JOR and the motor representation within face-M1 after iOVD is long time-dependent. Nasal obstruction affected the orofacial functions by delaying the JOR response and increasing the contraction force of the tongue-protruding muscles. These findings suggest changes in the orofacial environment may affect the masticatory function, which may influence the shape and development of the TMJ in growing rats.

Free Research Field

歯科矯正学