Department of Pulp Biology and Endodontics, Division of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan.
Department of Conservative Dentistry, University of Dental Medicine, Mandalay, Myanmar.
Photobiomodul Photomed Laser Surg. 2020 Jul;38(7):438-443. doi: 10.1089/photob.2019.4758.
This study aimed to examine the irrigant flow generated by laser-activated irrigation (LAI), in comparison with ultrasonic-activated irrigation (UAI) and syringe irrigation (SI), in the area beyond the ledge using particle image velocimetry (PIV). There was no reported study about cleaning efficacy of LAI beyond the ledge. Forty-nine J-shaped root canal models (40° curvature) were instrumented to no. 35/0.06, and a ledge, 2.5 mm deep, was created with no. 60/0.08 instrument at 5 mm from the apical foramen in each canal. The samples were irrigated with LAI [30 mJ/5 pulse per second (pps), 30 mJ/10 pps, 30 mJ/20 pps, 50 mJ/10 pps, 70 mJ/10 pps], UAI, and SI with a tip/needle insertion depth of 5 mm from the apical foramen ( = 7). PIV was performed with glass beads and a high-speed camera. Velocities were compared in the coronal and apical areas to the ledge, respectively. In the apical area, all LAI groups and UAI produced a higher velocity than that of SI, and LAI at 30 mJ/20 pps and 70 mJ/10 pps showed significantly higher velocity than that of UAI ( < 0.05). In the coronal area, LAI at 30 mJ/20 pps generated a significantly higher velocity than that of UAI and SI ( < 0.05). Velocity was significantly slower in the apical area than in the coronal area in UAI and SI ( < 0.05), but was similar between both areas in LAI except at 30 mJ/20 pps. Among tested laser settings, higher velocity was significantly achieved by LAI at 30 mJ/20 pps and 70 mJ/10 pps compared with UAI in the canal area beyond the ledge. SI generated lower fluid movement than LAI and UAI in both canal regions.
本研究旨在通过粒子图像测速法（PIV）比较激光激活冲洗（LAI）、超声激活冲洗（UAI）和注射器冲洗（SI）在牙本质肩台下方产生的冲洗剂流。目前尚无关于 LAI 在牙本质肩台下方清洁效果的报道。49 个 J 形根管模型（40°弯曲）用 35/0.06 器械扩至 35 号，在每个根管距根尖孔 5mm 处用 60/0.08 器械制备 2.5mm 深的牙本质肩台。用 LAI [30mJ/5 脉冲每秒（pps）、30mJ/10 pps、30mJ/20 pps、50mJ/10 pps、70mJ/10 pps]、UAI 和 SI 冲洗样本，尖端/针插入深度为距根尖孔 5mm（ = 7）。用玻璃珠和高速摄像机进行 PIV。分别比较了冠部和根尖区域到牙本质肩台的速度。在根尖区域，所有 LAI 组和 UAI 产生的速度均高于 SI，30mJ/20 pps 和 70mJ/10 pps 的 LAI 产生的速度明显高于 UAI（ < 0.05）。在冠部区域，30mJ/20 pps 的 LAI 产生的速度明显高于 UAI 和 SI（ < 0.05）。UAI 和 SI 在根尖区域的速度明显慢于冠部区域（ < 0.05），但 LAI 在两个区域的速度相似，除 30mJ/20 pps 外。在测试的激光设置中，与 UAI 相比，30mJ/20 pps 和 70mJ/10 pps 的 LAI 可显著提高牙本质肩台下方根管区域的速度。SI 在两个根管区域的流体运动速度均低于 LAI 和 UAI。
