Mattiello Fabiano Dalla Lana, Coelho Alan Augusto Kalife, Martins Odair Pimentel, Mattiello Rodrigo Dalla Lana, Ferrão Júnior José Peixoto
Department of Prosthetic and Restorative Dentistry, Dental School, Federal University of Mato Grosso do Sul, Campo Grande, MS, Brazil.
Braz Dent J. 2011;22(5):398-403. doi: 10.1590/s0103-64402011000500009.
New periodontal disease treatments are needed to prevent infection progression. Photodynamic therapy (PDT) is one of the greatest pledges for this purpose. It involves the use of light of specific wavelength to activate a nontoxic photosensitizing agent in the presence of oxygen for eradication of target cells, and can be used for photokilling of microorganisms. This study evaluated in vitro the photodynamic effect of 0.01% toluidine blue-O (TBO) in combination with an AlGaInP diode laser light source on Aggregatibacter actinomycetemcomitans (A.a.) and Streptococcus sanguinis (S.s.). Suspensions (2 mL) containing A.a. and S.s. at 1.5 x 108 CFU/mL concentration were prepared and divided into 3 groups: Control group (no treatment), Dye group (inoculum and TBO for 5 min) and Dye/Laser group (inoculum, TBO for 5 min and laser for 3 min). Next, a dilution for subsequent subculture in 20 mL of Trypic Soy Agar (A.a) and Brucella Agar (S.s.) in Petri dishes (Pourplate Method) was done. Incubation of A.a. in microaerophilia and S.s. in aerobiosis at 35oC for 48 h was performed for subsequent visual counting of CFU/mL. Data were analyzed by one-way ANOVA and Tukey's HSD test at 5% significance level. For both strains, the control group showed a significantly higher (p<0.05) bacterial growth (1.5 x 108 CFU/mL), while the Dye group presented no significant reduction (p>0.05) in the CFU counts. The Dye/Laser group presented a significant decrease in the CFU counts (p<0.05) compared with the Control group (61.53% for A.a. and 84.32% for S.s.). It may be concluded that PDT was effective in reducing the numbers of A.a. and S.s. in vitro.
需要新的牙周病治疗方法来防止感染进展。光动力疗法（PDT）是实现这一目标的最大希望之一。它涉及在氧气存在下使用特定波长的光来激活无毒的光敏剂以根除靶细胞，并且可用于光杀灭微生物。本研究在体外评估了0.01%甲苯胺蓝-O（TBO）与铝镓铟磷二极管激光光源联合对伴放线聚集杆菌（A.a.）和血链球菌（S.s.）的光动力效应。制备了浓度为1.5×108 CFU/mL的含有A.a.和S.s.的悬浮液（2 mL），并分为3组：对照组（未处理）、染料组（接种物和TBO处理5分钟）和染料/激光组（接种物、TBO处理5分钟和激光处理3分钟）。接下来，进行稀释以便在培养皿中用20 mL胰蛋白胨大豆琼脂（用于A.a.）和布鲁氏琼脂（用于S.s.）进行后续传代培养（倾注平板法）。将A.a.在微需氧条件下以及S.s.在需氧条件下于35℃孵育48小时，以便随后对CFU/mL进行目视计数。数据采用单因素方差分析和Tukey's HSD检验进行分析，显著性水平为5%。对于两种菌株，对照组显示出显著更高（p<0.05）的细菌生长（1.5×108 CFU/mL），而染料组的CFU计数没有显著降低（p>0.05）。与对照组相比，染料/激光组的CFU计数显著降低（p<0.05）（A.a.为61.53%，S.s.为84.32%）。可以得出结论，光动力疗法在体外有效减少了A.a.和S.s.的数量。
