The mechanical properties of human teeth structure

2018 Fiscal Year Final Research Report

• Project/Area Number: 25463021
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Prosthodontics/ Dental materials science and
• Research Institution: Showa University
• Principal Investigator: INOUE Toshiko 昭和大学, 歯学部, 研究補助員 (90398701)
• Co-Investigator(Kenkyū-buntansha): 山本 雅人 昭和大学, 教養部, 准教授 (50277844) ; 齊藤 誠 昭和大学, 歯学部, その他 (60420915)
• Project Period (FY): 2013-04-01 – 2019-03-31
• Keywords: 歯 / 歯質 / 象牙質 / 強度特性 / 歯根 / 人歯

Outline of Final Research Achievements

The dentin-enamel junction is a unique biological interface between the enamel and dentin in teeth. We investigated the anisotropic tensile strength of this region in human teeth by examining tensile loading in parallel versus perpendicular orientations. We found that the presence of structural anisotropy in dentin-enamel junctions. Additionally, transparent dentin is known to develop in tooth roots with aging. In this study, we investigated the structural and mechanical properties of the transparent dentin region. Transparent dentin is weaker than normal dentin, which may explain the occurrence of root dentin fractures in aged individuals. Moreover, we observe the surface of dentin slabs exposed to ultraviolet light from an excimer lamp. The water contact angle was measured. UV-irradiated dentin exhibited increased surface wettability. We confirm that irradiation with ultraviolet light is a useful method of surface modification.

Free Research Field

歯学

Academic Significance and Societal Importance of the Research Achievements

口腔領域は摂食をはじめとして多くの重要な機能を担っており，歯の強度特性を検討することは歯科医療においても修復物設計の指針となり，重要であると思われる．超高齢化社会の到来とともに，歯を保存することが高齢者のQOLを維持するために重要な要因であることが認識されている．歯がどのような強度分布をしているかを知ることは高齢者などの歯の破折を防ぐための修復物の設計には必要不可欠な情報であり，意義の高いことと考えられる．