Nunes Maralize Ribeiro, Mello Isabel, Franco Gilson Cesar Nobre, de Medeiros João Marcelo Ferreira, Dos Santos Silvana Soléo Ferreira, Habitante Sandra Márcia, Lage-Marques José Luiz, Raldi Denise Pontes
Department of Endodontics, University of Taubaté, São Paulo, Brazil.
Photomed Laser Surg. 2011 Dec;29(12):803-8. doi: 10.1089/pho.2011.2995. Epub 2011 Jul 26.
Photodynamic therapy (PDT) is a new technique introduced in endodontics that combines the action of a photosensitizer (dye) and a low intensity light source. Currently, there are no PDT studies evaluating the microbial disinfection of root canals in order to compare the effects of light delivery systems in the photosensitizer activation. The aim of this study was to evaluate the PDT effectiveness in reducing Enterococcus faecalis, with and without the aid of an intracanal optical fiber.
Extracted single-rooted teeth were selected, instrumented, inoculated with E. faecalis and divided into six groups: one control group (untreated), one conventionally-treated group (1% NaOCl irrigation) and four PDT-treated groups. Irradiation (diode laser) was performed with (OF) or without an intracanal optical fiber (NOF) using two different irradiation times: 1 min and 30 sec (IT(90)) or 3 min (IT(180)). Samples were collected before and after testing procedures and CFU/mL was determined.
The greatest reduction of E. faecalis (99.99%) was achieved with irrigation with 1% NaOCl. PDT also significantly reduced E. faecalis in the following decreasing order: OF/IT(180), NOF/IT(180), OF/IT(90) and NOF/IT(90), with no significant statistical difference among the groups.
These results suggest that PDT was effective against E. faecalis, regardless of the use of an intracanal optical fiber.
光动力疗法（PDT）是牙髓病学中引入的一项新技术，它将光敏剂（染料）与低强度光源的作用相结合。目前，尚无评估根管微生物消毒效果以比较光传递系统对光敏剂激活作用的光动力疗法研究。本研究的目的是评估在有无根管内光纤辅助的情况下，光动力疗法对减少粪肠球菌的有效性。
选取拔除的单根牙，进行根管预备，接种粪肠球菌，分为六组：一组为对照组（未治疗），一组为传统治疗组（用1%次氯酸钠冲洗），四组为光动力疗法治疗组。使用二极管激光进行照射，有（OF）或无根管内光纤（NOF），采用两种不同的照射时间：1分钟和30秒（IT(90)）或3分钟（IT(180)）。在测试程序前后收集样本并测定CFU/mL。
用1%次氯酸钠冲洗时粪肠球菌减少最多（99.99%）。光动力疗法也显著减少了粪肠球菌，降序排列如下：OF/IT(180)、NOF/IT(180)、OF/IT(90)和NOF/IT(90)，各组间无显著统计学差异。
这些结果表明，无论是否使用根管内光纤，光动力疗法对粪肠球菌均有效。
