Development of novel ex vivo biofilm model using oral samples

• Project/Area Number: 17K17133
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Conservative dentistry
• Research Institution: Osaka University
• Principal Investigator: Maezono Hazuki 大阪大学, 歯学部附属病院, 助教 (00613390)
• Research Collaborator: Haapasalo Markus , 教授
• Project Period (FY): 2017-04-01 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥4,030,000 (Direct Cost: ¥3,100,000、Indirect Cost: ¥930,000); Fiscal Year 2018: ¥2,340,000 (Direct Cost: ¥1,800,000、Indirect Cost: ¥540,000); Fiscal Year 2017: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
• Keywords: バイオフィルム / ex vivo

Outline of Final Research Achievements

We prepared experimentally biofilms from oral samples ex vivo using several models. In all models, bacterial numbers increased over time. We exermined their qualitative characteristics with conforcal laser scanning microscope and found that biofilms were composed of vital cells during the observation period. Also, we exermined biofilms micromorphology with scanning electron microscope and found biofilms were getting thicker and complex component over time. Moreover, main bacterial components were similar with all the models we tested by pyrosequence analysis.
From these results we obtained from this project, we could obtain experimentally-made ex vivo biofilms using oral samples whose bacterial numbers increased over time and biofilms got matured.

Academic Significance and Societal Importance of the Research Achievements

口腔内で起こる、う蝕や歯周炎といった疾患の主たる原因は口腔内に存在するバイオフィルムである。これらについて研究を進めていくことは疾患の予防や治療に欠かせない。研究を進めていく上で、実際の口腔内で実験を進めていくことは理想的ではあるが、現実的ではない。簡便に実験室で実際の口腔内に類似した環境でバイオフィルムを作製することができれば新薬の開発等につながり、理想的な研究環境が得られる。今回の研究結果はこれらにつながる学術的意義や社会的意義に富んだものと言える。

Research Products

• [Int'l Joint Research] ブリティッシュコロンビア大学(カナダ)
• [Journal Article] Development of a root canal treatment model in the rat (2017)
  • Author(s): Yoneda Naomichi、Noiri Yuichiro、Matsui Saori、Kuremoto Katsutaka、Maezono Hazuki、Ishimoto Takuya、Nakano Takayoshi、Ebisu Shigeyuki、Hayashi Mikako
  • Journal Title: Scientific Reports Volume: 7 Issue: 1 Pages: 3315-3315
  • DOI: 10.1038/s41598-017-03628-6
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] 口腔サンプルを用いた新規ex vivoバイオフィルムモデルの開発 (2018)
  • Author(s): 前薗 葉月，クランリアン キッティピット，外園 真規，松井 沙織， 米田 直道，野杁 由一郎，林 美加子
  • Organizer: 第39回日本歯内療法学会学術大会
• [Presentation] High-frequency Waves Promote Periapical Healing by Inducing Cell Growth Factors (2018)
  • Author(s): Matsui S, Noiri Y, Hayashi M, Maezono H, Kuremoto K, Yoneda N, Ebisu S, Yumoto H, Matoba K, Ishimoto T, Nakano T
  • Organizer: The 96th General Session of the International Association of Dental Research
  • Int'l Joint Research
• [Presentation] Dentin Permeability and Bactericidal Effects of MDPB-containing Cavity Disinfectant (2018)
  • Author(s): Hirose N, Kitagawa H, Maezono H, Hayashi M, Haapasalo M, Imazato S
  • Organizer: The 96th General Session of the International Association of Dental Research
  • Int'l Joint Research
• [Presentation] Assessment of novel ex vivo biofilm models using oral sample (2018)
  • Author(s): Klanliang K, Maezono H, Yamaguchi M, Sotozono M, Matsui S, Yoneda N, Noiri Y, Hayashi M
  • Organizer: The International Federation of Endodontic Associations 11th World Endodontic Congress
  • Int'l Joint Research
• [Presentation] ラット根管治療モデルを用いた高周波根尖療法の評価 (2018)
  • Author(s): 松井沙織、前薗葉月、呉本勝隆、米田直道、恵比須繁之、湯本浩通、的場一成、石本卓也、中野貴由、野杁由一郎、林美加子
  • Organizer: 第149回日本歯科保存学会2018年度秋季学術大会
• [Presentation] Effect of concentration / application time of sodium hypochlorite using ex vivo polymicrobial biofilm model (2017)
  • Author(s): Maezono H, Noiri Y, Shen Y, Ebisu S, Hayashi M, Haapasalo M
  • Organizer: 国際歯科研究学会日本部会（JADR）