Pulp evaporation and root canal sterilization in inaccessed root canals using high-frequency current

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K09908
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 57030:Conservative dentistry-related
• Research Institution: Hokkaido University
• Principal Investigator: Sugaya Tsutomu 北海道大学, 歯学研究院, 特任教授 (10211301)
• Co-Investigator(Kenkyū-buntansha): 西田 絵利香 北海道大学, 大学病院, 医員 (50779882)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 高周波電流 / 根尖狭窄部 / 焼灼 / 蒸散 / 殺菌 / 根尖性歯周炎

Outline of Final Research Achievements

Simulated root canals made of dentin were energized at 225V and were filled, and its sealing abilities were evaluated. As a result, C and O disappeared from the root canal wall, and only Ca and P were detected, resulting in a porous lava-like structure. When the root canal was filled with Metaseal Soft paste, it penetrated into the lava-like pores and formed tags into the dentinal tubules. When electricity was applied at 5-second intervals, the temperature increase on the tooth root surface reached a maximum of 55°C after 10 times of electricity. When a biofilm of S. mutans was formed in a simulated root canal and electricity was applied, all bacteria disappeared in 5 seconds. Even when apical periodontitis was induced in dogs and electricity was applied 2.5 mm from the root apex to the coronal side without root canal preparation, apical bone defects were reduced or disappeared in almost 100%.

Free Research Field

歯内療法学

Academic Significance and Societal Importance of the Research Achievements

歯髄炎における抜髄時間が短縮化され術後疼痛が著しく減少すること、さらに根尖性歯周炎の成功率が向上することが期待され、しかもいずれの治療に用いる場合でも術式はきわめて容易であり広く普及する治療法になると考えられる。このことは歯の保存がより広く行われることにつながり、口腔機能の維持に大きく貢献するとともに健康寿命の延伸となり、医療費の抑制にも役立つと思われる。