Establishment of three-dimensional LAI fluid flow vortex behavior, elucidation of cleaning efficiency and safety, and development of clinical application techniques in complex root canal systems

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K23019
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0907:Oral science and related fields
• Research Institution: Tokyo Medical and Dental University
• Principal Investigator: Kouno Akira 東京医科歯科大学, 大学院医歯学総合研究科, 非常勤講師 (50880209)
• Project Period (FY): 2020-09-11 – 2023-03-31
• Keywords: Endodontics / Root canal irrigation / Er:YAG laser / LAI / PUI / Fractured instruments / SEM / Kinetics

Outline of Final Research Achievements

In root canal treatment, irrigation is one of the essential techniques. This study focuses on laser-activated irrigation (LAI) utilizing Er:YAG laser. Compared to conventional syringe irrigation and ultrasonic irrigation methods, LAI demonstrated superior cleaning efficacy. It was found that increasing the laser tip diameter, raising the output power, and positioning the tip closer to the target resulted in higher cleaning effectiveness. Research conducted using a high-speed camera and simulated root canals with an instrument revealed that the number and velocity of vapor bubbles generated by LAI were significantly higher than those produced by conventional irrigation methods, indicating a higher cleaning effect.

Free Research Field

歯内療法学分野

Academic Significance and Societal Importance of the Research Achievements

根管治療は日常の臨床において行うケースが多く、またその成功率も術者により差がででていることが現状である。根管洗浄の応用は成功率にも影響しており、成功率があがることは再治療も少なくなるため、患者の負担軽減となる。本研究では、従来行われていた根管洗浄法よりも優れた清掃効果を示す結果となった。LAIは難しいテクニックを使用せず、短時間で非侵襲的と予想されるため、患者負担は軽減されると考えられる。また破折器具を想定した研究では、今まで清掃効果が確認できなかった部位への洗浄効果を示し、破折器具の除去の必要性もなくなる可能性があるため非常に革新的で有意義なものであった。