Master Program, Ibirapuera University, Av Interlagos 1329, Chácara Flora, São Paulo, SP, 04661-100, Brazil.
Special Laboratory of Lasers in Dentistry (LELO), Department of Restorative Dentistry, Dentistry School, University of São Paulo, Av Professor Lineu Prestes 2227, Cidade Universitária, São Paulo, SP, 05508-000, Brazil.
Photodiagnosis Photodyn Ther. 2017 Dec;20:248-252. doi: 10.1016/j.pdpdt.2017.10.024. Epub 2017 Oct 31.
In Endodontics, photosensitizers' such as methylene blue and toluidine blue have been used in Photodynamic Therapy due to their positive results. However, they can stain the dentin from the root canal after Photodynamic Therapy (PDT). The present in vitro study aimed to evaluate different stain removal protocols from root canal after PDT using methylene blue (MB) dye. After mechanical preparation of the root canal of 40 uni-radicular human teeth, PDT was performed using 0,01% MB with parameters of 3min of pre-irradiation and a diode laser irradiation emitting at 660nm, 40mW, 4min, 9.6J. After PDT, different protocols of MB removal were performed: Group 1 - control (0.9% saline solution); Group 2 - sodium hypochlorite (2.5% NaOCl); Group 3-17% ethylenediamine tetraacetic acid (EDTA); Group 4 - passive ultrasonic irrigation (PUI); The color of the dentin of the root canal was measured, before, immediately after the PDT and immediately after the cleaning using a spectrophotometer. The ΔE values found were statistically compared using the ANOVA and Tukey's tests (α=0.05). All the treatments lead to some cleaning of root canal after PDT, however, none of the treatments tested completely removed all staining caused by MB photosensitizer of the root canal. Among the treatments tested, PUI and Hypochlorite 2.5% promoted greater cleaning, with no statistically significant difference between them. In conclusion, within the protocols tested in the present study, no treatments were able to completely remove MB staining of the root canal after PDT.
在牙髓学中，由于亚甲蓝和甲苯胺蓝等光敏剂在光动力疗法中的积极效果，它们已被用于光动力疗法。然而，在光动力疗法（PDT）后，它们会使根管内的牙本质染色。本体外研究旨在评估使用亚甲蓝（MB）染料从 PDT 后的根管中去除不同染色的方案。在对 40 颗单根人牙的根管进行机械准备后，使用 0.01%MB 进行 PDT，预辐照 3 分钟，二极管激光以 660nm、40mW、4 分钟、9.6J 进行辐照。PDT 后，进行不同的 MB 去除方案：第 1 组-对照组（0.9%生理盐水溶液）；第 2 组-次氯酸钠（2.5%NaOCl）；第 3 组-17%乙二胺四乙酸（EDTA）；第 4 组-被动超声冲洗（PUI）；在使用分光光度计测量根管牙本质的颜色之前、PDT 后立即以及清洁后立即测量。使用方差分析和 Tukey 检验（α=0.05）对发现的ΔE 值进行统计学比较。所有治疗方法都导致 PDT 后根管有一定程度的清洁，但没有一种治疗方法能完全去除根管内 MB 光敏剂引起的所有染色。在所测试的治疗方法中，PUI 和 2.5%次氯酸钠促进了更大的清洁效果，它们之间没有统计学上的显著差异。总之，在所测试的方案中，没有一种治疗方法能够完全去除 PDT 后根管内的 MB 染色。
