Laser Research Center of Dentistry, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
Microbiology Department, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
J Appl Oral Sci. 2014 Apr;22(2):80-4. doi: 10.1590/1678-775720130038.
Streptococcus mutans is the main etiological agent for dental caries. Recently, photodynamic therapy (PDT) has been introduced as a new modality in bacterial decontamination.
This in vitro study was carried out to evaluate the susceptibility of Streptococcus mutans to antibacterial PDT using two different photosensitizers and light sources.
Standard suspensions of S. mutans were exposed to laser light at 662 nm and Radachlorin or LED 630 nm in combination with Toluidine blue O (TBO). Radiation-only groups, photosensitizer alone, and groups with no treatment were used as controls. Bacterial suspension from each treatment was subcultured onto the surface of Mueller-Hinton agar plates and bacterial growth was assessed. The results were analyzed by analysis of variance and Tukey test (p<0.05).
PDT with TBO and Radachlorin® significantly reduced S. mutans viability, whereas no difference was observed between two groups of PDT. In the groups treated just with the photosensitizer or irradiated alone, no significant reduction of S. mutans colonies was observed.
S. mutans colonies were susceptible to either 662 nm laser or LED light in the presence of Radachlorin and TBO respectively with no priority.
本体外研究旨在评估两种不同光敏剂和光源的抗菌光动力疗法（PDT）对变形链球菌的敏感性。
标准变形链球菌悬液分别用 662nm 激光和 Radachlorin 或 LED 630nm 联合甲苯胺蓝 O（TBO）进行照射。仅照射组、单独使用光敏剂组和无处理组作为对照。将每种处理的细菌悬液接种到 Mueller-Hinton 琼脂平板表面，评估细菌生长情况。结果采用方差分析和 Tukey 检验（p<0.05）进行分析。
TBO 和 Radachlorin®的 PDT 显著降低了变形链球菌的活力，而两种 PDT 组之间没有差异。单独使用光敏剂或仅照射的组中，变形链球菌菌落没有明显减少。
在分别存在 Radachlorin 和 TBO 的情况下，662nm 激光或 LED 光对变形链球菌菌落均敏感，没有优先性。
