Longitudinal Changes of Occlusal Facets and Contact Areas over Thirty Years

• Published in: Nihon Hotetsu Shika Gakkai Zasshi Vol. 48; no. 3; pp. 384 - 393
• Main Authors: Ogawa, Takumi, Yamanaka, Satoshi, Araki, Jiro, Hitomi, Yuhko, Shigeta, Yuhko, Hirai, Shinya, Nakao, Katsuhiko, Fukushima, Shunji
• Format: Journal Article
• Language: Japanese
• Published: Japan Prosthodontic Society 2004
• Subjects: eccentric mandibular position; intercuspal position; longitudinal change; occlusal contact area; occlusal facet
• ISSN: 0389-5386; 1883-177X
• DOI: 10.2186/jjps.48.384

Purpose: This study investigated morphological changes to occlusal facets and contact areas over a 30-year period in one subject. Methods: Occlusal facets and contact areas at intercuspal and eccentric mandibular positions were recorded using a silicone impression material (Bite checker, GC) when the patient was 25, 39 and 55 years old. Results: The number of occlusal facets and contact areas in the intercuspal position increased with age, particularly at the molars. Contact areas in the most retruded contact position were predominantly found at the second molar in all stages. The number of contact areas in the protrusive movements decreased with age at the anterior teeth and the premolars, but increased at the molars. The number of working-side contact areas in the lateral movement to the right side did not indicate any obvious tendencies with age, but the corresponding number in the lateral movement to the left side increased gradually. Conversely, the number of balancing-side contact areas at the molars in 1-2 mm lateral positions from the intercuspal position on the both sides increased with age and was substantially larger than on the working-side. Conclusions: Morphological changes to occlusal facets over a 30-year period in the subject were cosiderably extensive at the molars, and in particular, contact areas in the intercuspal position had an influence on the occlusal facets.