Cyclic fatigue property of titanium alloy as dental implant

2019 Fiscal Year Final Research Report

• Project/Area Number: 18K17103
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 57040:Regenerative dentistry and dental engineering-related
• Research Institution: Tokyo Dental College
• Principal Investigator: Takano Tomofumi 東京歯科大学, 歯学部, 講師 (40615382)
• Project Period (FY): 2018-04-01 – 2020-03-31
• Keywords: チタン / チタン合金 / インプラント / 疲労強度

Outline of Final Research Achievements

The objective of this study was to investigate the cyclic fatigue properties of titanium alloy (Ti-6Al-4V, Ti-6Al-7Nb).
Yield force under the static loading tests (YS) was measured on five specimens of each alloy using the universal testing machine. Yield force under the cyclic loading test (YC) was measured by the staircase method. YS of Ti-6Al-4V and Ti-6Al-7Nb were 1463±93N and 1405±79N, respectively. YC of these were 870±58N and 853±202N, respectively. YC of Ti-6Al-4V decreased to 59.4% of those of YS. YC of Ti-6Al-7Nb decreased to only 60.7% of those of YS.The yield force under cyclic loading of Ti-6Al-4V and Ti-6Al-7Nb was 40% lower than the yield force under the static loading, which was similar to Cp-Ti grade 4. However, while the yield force under cyclic loading of Cp-Ti was less than 700 N, these values of Ti-6Al-4V and Ti-6Al-7Nb are more than 800N, leading to be acceptable for a patient with narrow residual ridge.

Free Research Field

歯科補綴学

Academic Significance and Societal Importance of the Research Achievements

インプラント材料としての純チタンおよびチタン合金の疲労特性については不明な点が多いが、本研究においてチタン合金の疲労特性を明らかにすることで、インプラント材料の選択に際し、顎堤の幅が狭い症例に適した細いインプラント材料の選択基準に示唆を与え、臨床応用上の1つの指針につながることに意義がある。また、本研究結果は歯科分野にとどまらず、チタンおよびチタン合金の疲労メカニズムの解明という点で研究者にとってもチタンおよびチタン合金の表面処理と疲労強度の関係を考察する一助になると考えられる。