Control of complicated root canal system of primary teeth: Clarification of reliable method for root resorption control and repair mechanism on resorbed part

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K11951
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Orthodontics/Pediatric dentistry
• Research Institution: Hokkaido University
• Principal Investigator: YAWAKA YASUTAKA 北海道大学, 歯学研究院, 教授 (60230603)
• Co-Investigator(Kenkyū-buntansha): 中村 光一 北海道大学, 歯学研究院, 助教 (50580932)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 歯学 / 乳歯 / 根管治療 / 根管洗浄 / 水酸化カルシウム製剤 / ｐH / 歯根吸収

Outline of Final Research Achievements

Regarding the root canal treatments, it was showed that the important factors of the control of complicated root canal system of primary teeth were the root canal irrigation with ultrasonic and the root canal medication by calcium hydroxide (Ca(OH)2).
We constructed a root resorption model in rat molar in animal experiment, and observed histologically the effects of Ca(OH)2 on root resorption. The effects of Ca(OH)2 showed inhibition of root resorption and occurrence of cementum deposition. We think cementum deposition is one of repair mechanisms on resorbed part.
We could construct a root resorption model in cell culture. But we do not reach the step as to investigate effects of Ca(OH)2 due to bad reproducibility.

Free Research Field

医歯薬学

Academic Significance and Societal Importance of the Research Achievements

乳歯の根管治療は、その複雑な根管系により難しいといわれている。今回の研究成果により、難しいといわれている乳歯根管治療の予後向上の可能性が示された。小児における齲蝕は減少傾向にあるとはいえ、根管治療が必要となる重篤な齲蝕や外傷は存在しており、健全な成長発育を理想とする小児において、口腔機能の維持増進は重要な点の一つである。この口腔機能の維持増進は、健全な歯、歯列、咬合が必須であり、その点からも、大きな意義を有する結果となった。