Clinic for Operative Dentistry, Periodontology and Preventive Dentistry, RWTH Aachen University, Pauwelsstrasse 30, Aachen 52074, Germany.
Clinic for Operative Dentistry, Periodontology and Preventive Dentistry, RWTH Aachen University, Pauwelsstrasse 30, Aachen 52074, Germany.
Photodiagnosis Photodyn Ther. 2021 Sep;35:102476. doi: 10.1016/j.pdpdt.2021.102476. Epub 2021 Aug 3.
Thermal photodynamic disinfection procedures have been proposed for adjunctive endodontic treatment. This study assessed photothermal disinfection relative to root dentin temperature and the thermal effects of simulated periodontal blood flow.
Thirty freshly extracted human single-rooted teeth were prepared endodontically using a 45/.02 master apical file. The root surfaces were coated with wax and covered with thermoforming sheets, leaving a circumferential space of 0.25 mm after wax removal. The sheets were perforated to allow fluid circulation through the simulated periodontal space. Irradiation was performed in two groups of 30: I, 810 nm laser (1.5 W, continuous wave), 4 × 5 s; II, photothermal group: indocyanine green and 810 nm laser (200 mW, continuous wave), 20 s. Thermographic measurements were performed at different water flow rates (6, 2.6, 0 mL/min) with a baseline temperature of 37 °C. Nonparametric statistical analysis was performed (Wilcoxon).
The highest temperature change (median 7.52 °C, range 0.82-18.32 °C) was with 810 nm laser irradiation in group I, without any simulated blood flow. Fluid circulation resulted in a significant reduction in temperature changes in this group (median 2.14 °C, range 0.37-9.83 °C; p < 0.05). The lowest temperature changes were in the photothermal group with a water flow rate of 6 mL/min (median 0.79 °C, range 0.00-3.88 °C; p < 0.05).
Photothermal disinfection of root canals can increase root canal dentin temperatures, but periodontal fluid circulation has a cooling effect on the outer root surface, reducing the risk of potential thermal injury to periodontal tissue.
热光动力消毒程序已被提议作为辅助根管治疗的方法。本研究评估了光热消毒相对于根管牙本质温度和模拟牙周血流的热效应。
30 颗新鲜离体人单根牙采用 45/.02 号根管锉进行根管预备。根面涂蜡，用热成型片覆盖，去除蜡后留下 0.25mm 的环形间隙。薄片穿孔，使模拟牙周间隙的液体循环。照射在两组 30 个样本中进行：I 组，810nm 激光（1.5W，连续波），4×5s；II 组，光热组：吲哚菁绿和 810nm 激光（200mW，连续波），20s。在基线温度为 37°C 的情况下，以 6、2.6、0mL/min 的不同水流速度进行热成像测量。采用非参数统计分析（Wilcoxon）。
在没有模拟血流的情况下，I 组中 810nm 激光照射产生的温度变化最大（中位数 7.52°C，范围 0.82-18.32°C）。在该组中，流体循环导致温度变化显著降低（中位数 2.14°C，范围 0.37-9.83°C；p<0.05）。在水流速度为 6mL/min 的光热组中，温度变化最低（中位数 0.79°C，范围 0.00-3.88°C；p<0.05）。
根管的光热消毒可以提高根管牙本质的温度，但牙周液循环对根尖表面有冷却作用，降低了对牙周组织潜在热损伤的风险。
