The Movement of the Chin during Mastication

• Published in: Nihon Hotetsu Shika Gakkai Zasshi Vol. 39; no. 6; pp. 1132 - 1141
• Main Authors: Kumagai, Hiroshi, Hirano, Yasuyoshi, Minakuchi, Syunsuke, Sekita, Toshiaki, Suzuki, Tetsuya, Kobayashi, Ken-ichi, Nagao, Masanori
• Format: Journal Article
• Language: English; Japanese
• Published: Japan Prosthodontic Society 1995
• Subjects: chin; mandibular movement; mastication; soft tissue
• ISSN: 0389-5386; 1883-177X
• DOI: 10.2186/jjps.39.1132

The purpose of this study was to evaluate suitability of the soft tissue on the chin as a reference point in measuring masticatory movements. The movements of the chin and a lower incisor during mastication were measured simultaneously using a real-time measuring system for three-dimensional movements of soft tissues (3-D Auto Tracking System). The results were as follows 1. Computer-based analysis was developed to divide the whole-chewing period into single stroke and determine the beginning of the opening, closing, occluding phase. 2. The chin movements were 1/60 sec slower than lower incisor movements at the beginning of the opening phase. 3. The chin movements were 1/60 sec faster than lower incisor movements at the beginning of the occluding phase. The results obtained in this study indicate that the soft tissue on the chin was suitable as a reference point in measuring masticatory movements.