Furtado Guilherme Silva, Paschoal Marco Aurélio Benini, Santos Grenho Liliana do Carmo, Lago Andréa Dias Neves
Dental School, Federal University of Maranhão - UFMA, Av. dos Portugueses, 1966, Bacanga, 65080-805, Brazil.
Department of Child and Adolescent Oral Health, Federal University of Minas Gerais - UFMG, Av. Antônio Carlos, 6627, Dental School, Campus Pampulha, Belo Horizonte, MG, 31270-901, Brazil.
Photodiagnosis Photodyn Ther. 2020 Sep;31:101884. doi: 10.1016/j.pdpdt.2020.101884. Epub 2020 Jun 23.
Antimicrobial photodynamic therapy (aPDT) has emerged as a promising antimicrobial treatment to control microorganisms including those involved in oral diseases, especially dental caries. Hence, the aim of this study was to evaluate the influence of aPDT - pre-irradiation time (PIT), at different periods, on antimicrobial rate of Streptococcus mutans (S. mutans). A standard suspension of S. mutans UA159 was prepared and submitted at sensitization of 0.005 % methylene blue (MB) for 0, 1, 3 and 5 min (G1 - G4 groups, respectively) and irradiated with a red laser (660 nm; 321 J/cm; 9 J; 90 s) afterward. A control group using PBS instead of MB was performed as well (G5). The number of colony-forming units (CFU)/mL was recorded, transformed into log and analyzed by ANOVA and Tukey's test at a cutoff value at 0.05. Overall, the aPDT groups tested achieved a bacterial reduction > 1-log when compared to G5 (p < 0.05) with no statistical difference among the different PIT tested. The need of PIT before aPDT application deserves attention, since its time reduction implies on shorter clinical approaches without compromising the photodynamic antibacterial efficacy in the in vitro parameters employed.
抗菌光动力疗法（aPDT）已成为一种有前景的抗菌治疗方法，用于控制包括那些与口腔疾病（尤其是龋齿）相关的微生物。因此，本研究的目的是评估不同时期的aPDT预照射时间（PIT）对变形链球菌（S. mutans）抗菌率的影响。制备了变形链球菌UA159的标准悬液，并分别在0.005%亚甲蓝（MB）中进行0、1、3和5分钟的敏化处理（分别为G1 - G4组），随后用红色激光（660 nm；321 J/cm²；9 J；90秒）照射。还设立了一个使用PBS代替MB的对照组（G5）。记录菌落形成单位（CFU）/mL的数量，转化为对数，并通过ANOVA和Tukey检验进行分析，临界值为0.05。总体而言，与G5组相比，所测试的aPDT组实现了>1个对数的细菌减少（p < 0.05），不同PIT测试组之间无统计学差异。在应用aPDT之前对PIT的需求值得关注，因为其时间的减少意味着临床操作更短，同时在所用的体外参数中不影响光动力抗菌效果。
