Stress-strain response under spherical nanoindentation of tooth enamel

• Project/Area Number: 25861808
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Conservative dentistry
• Research Institution: Showa University
• Principal Investigator: OGINO REINA 昭和大学, 歯学部, 助教 (80585779)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥4,030,000 (Direct Cost: ¥3,100,000、Indirect Cost: ¥930,000); Fiscal Year 2015: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2014: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2013: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
• Keywords: エナメル質 / 物性 / 応力ひずみ曲線 / オフィスホワイトニング / ナノインデンテーション / エナメル小柱 / 球状圧子

Outline of Final Research Achievements

The aim of this study was to investigate the mechanical properties of bleached enamel and obtain stress-strain curves using spherical nanoindentation. Based on the hierarchical structure, nanoscale analysis is critical for the measurement of enamel crystals mechanical property. The stress-strain curves were obtained for the conical indenters for fused quartz and untreated enamel. The continuous stress-strain curves were measurable for untreated and in-office bleached (35 % hydrogen peroxide with halogen lamp irradiation 3 minutes x 3 times ; OB) enamel. The yield force was observed clearly in enamel stress-strain curves. The analysis of data obtained from partial unloading method with conical indenter tip revealed the stress-strain response by nanoindentation of enamel crystals without the effect of enamel sheath protein so that nanoscale mechanical properties on enamels with or without OB were comparable at material level.

Research Products

• [Journal Article] Nanomechanical properties and molecular structures of in vitro mineralized tissues on anodically oxidized titanium surfaces. (2014)
  • Author(s): Jang, I-. K., Tanaka, R., Wurihan, Suzuki, D., Shibata Y., Fujisawa, N., Tanimoto, Y., Ogura, K., Kamijo, R., Miyazaki, T.
  • Journal Title: Nanomedicine Volume: 10 Issue: 3 Pages: 629-637
  • DOI: 10.1016/j.nano.2013.09.007
  • Peer Reviewed
• [Journal Article] In vitro demineralization of tooth enamel subjected to two whitening regimes. (2013)
  • Author(s): Ogura K., Tanaka R., Shibata Y., Miyazaki T., Hisamitsu H.
  • Journal Title: Journal of the American Dental Association Volume: 144 Issue: 7 Pages: 799-807
  • DOI: 10.14219/jada.archive.2013.0190
  • Peer Reviewed
• [Presentation] Stress-strain response under spherical nanoindentation of bleached tooth enamel (2015)
  • Author(s): R. TANAKA, Y. SHIBATA, T. MIYAZAKI
  • Organizer: 6th International Conference on Mechanics of Biomaterials and Tissue
  • Place of Presentation: アメリカ合衆国
  • Year and Date: 2015-12-10
  • Int'l Joint Research
• [Presentation] ナノインデンテーション法による漂白エナメル質の物性解析 (2015)
  • Author(s): 田中 玲奈 柴田 陽 糸瀬 明希 宮﨑 隆
  • Organizer: 日本歯科理工学会第66回秋季学術講演会
  • Place of Presentation: タワーホール船堀
  • Year and Date: 2015-10-03
• [Presentation] 球状圧子を用いたナノインデンテーションによるエナメル質の応力ひずみ特性 (2015)
  • Author(s): 田中 玲奈 柴田 陽 宮﨑 隆
  • Organizer: 日本歯科理工学会第65回春季学術講演会
  • Place of Presentation: 仙台市情報・産業プラザ
  • Year and Date: 2015-04-11
• [Presentation] 二種類のホワイト二ング処理によるエナメル質の耐酸性 (2014)
  • Author(s): 田中 玲奈，真鍋 厚史，宮﨑 隆
  • Organizer: 第140回日本歯科保存学会2014年度春季学術大会
  • Place of Presentation: びわ湖ホール
  • Year and Date: 2014-06-19 – 2014-06-20
• [Presentation] 準静的・動的ナノインデンテーションによるエナメル質のひずみ依存剛性 (2014)
  • Author(s): 田中 玲奈 柴田 陽 宮崎 隆
  • Organizer: 平成24年度私立大学戦略的研究基盤形成支援事業公開シンポジウム
  • Place of Presentation: 昭和大学
• [Presentation] エナメル小柱の準静的および動的物性評価 (2013)
  • Author(s): 田中 玲奈, 真鍋厚史, 宮崎 隆
  • Organizer: 第138回日本歯科保存学会2013年度春季学術大会
  • Place of Presentation: 福岡
• [Patent(Industrial Property Rights)] エナメル質石灰化促進セット (2014)
  • Inventor(s): 宮崎 隆、柴田 陽、田中 玲奈、薗井 秀次、繁澤 麻紗子
  • Industrial Property Rights Holder: 学校法人昭和大学
  • Industrial Property Rights Type: 特許
  • Filing Date: 2014-10-20
  • Acquisition Date: 2014-11-28