In vivo safety evaluation of novel radical disinfection technique –focusing on risk evaluation of carcinogenesis-

• Project/Area Number: 25861820
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Prosthodontics/ Dental materials science and
• Research Institution: Tohoku University
• Principal Investigator: HAYASHI Eisei 東北大学, 歯学研究科(研究院), 大学院非常勤講師 (60375102)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Project Status: Completed (Fiscal Year 2014)
• Budget Amount: ¥3,770,000 (Direct Cost: ¥2,900,000、Indirect Cost: ¥870,000); Fiscal Year 2014: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000); Fiscal Year 2013: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
• Keywords: ラジカル / 過酸化水素 / 殺菌 / オキシドール / 過酸化水素光分解殺菌 / ヒドロキシルラジカル / 生体安全性 / ラジカル殺菌

Outline of Final Research Achievements

In the disinfection treatment with photolysis of hydrogen peroxide, stabilizers added in commercially available oxydol products, which had been expected to be used in the final disinfection device as a source of hydrogen peroxide, could be denatured. In addition to hydroxyl radical, such denatured components could be a risk factor of carcinogenesis. In the present study examining in vivo local toxicity and the effect of laser light irradiation on the stabilizers, the following results were obtained. That is, 1) the disinfection treatment did not show any in vivo toxicity in local mucosal tissues, 2) laser light irradiation of oxydol products made stabilizers denatured, and 3) 3% hydrogen peroxide solution without stabilizers was proven to be stable. These results suggest that short-term treatment of periodontitis using the disinfection technique would be free from a risk of carcinogenesis when stabilizer-free hydrogen peroxide solution is used.

Research Products

• [Journal Article] Synergistic interaction between wavelength of light and concentration of H2O2 in bactericidal activity of photolysis of H2O2. (2015)
  • Author(s): Toki, T., Nakamura, K., Kurauchi, M., Kanno, T., Katsuda, Y., Ikai, H., Hayashi, E., Egusa, H., Sasaki, K., Niwano, Y.
  • Journal Title: Journal of Bioscience and Bioengineering Volume: 19(3) Issue: 3 Pages: 1358-1362
  • DOI: 10.1016/j.jbiosc.2014.08.015
  • NAID: 210000004988
  • Peer Reviewed
• [Journal Article] 1. In vitro bactericidal activity of photo-irradiated oxydol products via hydroxyl radical generation. (2013)
  • Author(s): Oyamada A, Ikai H, Nakamura K, Hayashi E, Kanno T, Sasaki K, Niwano Y.
  • Journal Title: Biocontrol Sci Volume: 18 Pages: 83-88
  • Peer Reviewed
• [Presentation] 過酸化水素光分解殺菌法における光源波長と過酸化水素濃度の相乗作用 (2014)
  • Author(s): 倉内 美智子, 唐木 俊英,中村 圭佑, 菅野 太郎, 勝田 悠介, 猪飼 紘代, 林 栄成, 佐々木 啓一, 江草 宏, 庭野 吉己
  • Organizer: 日本防菌防黴学会題41回年次大会
  • Place of Presentation: 東京
  • Year and Date: 2014-09-24 – 2014-09-25