Alves-Silva Esdras G, Bronzato Juliana D, Lopes Ana B S, Arruda-Vasconcelos Rodrigo, Louzada Lidiane M, De-Jesus-Soares Adriana, Marciano Marina A, Steiner-Oliveira Carolina, Gomes Brenda P F A
Piracicaba Dental School, State University of Campinas, Piracicaba, SP, Brazil.
Department of Dentistry, School of Dentistry, University of São Paulo, São Paulo, Brazil.
Lasers Med Sci. 2025 Apr 28;40(1):214. doi: 10.1007/s10103-025-04448-1.
To evaluate the effect of the agitation of an ultrasonic photosensitizer during the antimicrobial photodynamic therapy (aPDT) in reducing multispecies biofilm composed of E. faecalis, C. albicans, and E. coli and endotoxins (LPS) within the root canals. Thirty lower premolars were contaminated and randomly divided into three groups (n = 10). Group 1 (G1) used saline solution as a control, G2 (aPDT) used a photosensitizer (0.005% methylene blue with 3 min) applied into the root canal followed by a red laser (100 mW power, 9 J of energy, for 90 s), and G3 (aPDT + U) used 0.005% methylene blue activated by ultrasound for 20 s followed by the application of a red laser as described in G2. The effectiveness of each protocol was determined through colony forming units per milliliter count (CFU/mL), and the levels of LPS were quantified by using the Limulus Amoebocyte Lysate technique. The data was statistically analyzed at a 5% level of significance. Viable bacteria were detected in all three groups, with a mean of 2.82 × 10 CFU/mL. The saline group was not effective in reducing viable counts or LPS levels (P > 0.05). The aPDT group resulted in a 56.27% reduction compared to baseline samples and aPDT + U promoted a 56.97% reduction in viable microorganisms from the biofilm. LPS was detected in all samples with a mean of 18.84 EU/mL. Saline was not effective in reducing LPS levels (P > 0.05). aPDT was effective in reducing LPS levels (P < 0.05) with a mean of 1.7 EU/mL. aPDT + U promoted additional LPS removal compared to the aPDT group (P < 0.05), with a mean of 0.02 EU/mL. For both CFU and LPS analyses, aPDT and aPDT + U were more effective than the control group, while aPDT + U was more effective than aPDT. In conclusion, ultrasonic activation of the photosensitizer during the aPDT increased antimicrobial activity against a mature multispecies biofilm, while lowering the LPS levels.
为评估抗菌光动力疗法（aPDT）过程中超声激活光敏剂对减少根管内由粪肠球菌、白色念珠菌和大肠杆菌组成的多菌种生物膜及内毒素（脂多糖，LPS）的效果。选取30颗下颌前磨牙进行污染处理，并随机分为三组（n = 10）。第1组（G1）使用生理盐水作为对照，第2组（aPDT）将光敏剂（0.005%亚甲蓝，作用3分钟）注入根管，随后使用红色激光（功率100 mW，能量9 J，照射90秒），第3组（aPDT + U）使用0.005%亚甲蓝经超声激活20秒，随后如第2组所述施加红色激光。通过每毫升菌落形成单位计数（CFU/mL）确定各方案的有效性，并使用鲎试剂法对LPS水平进行定量。数据在5%的显著性水平上进行统计学分析。所有三组均检测到活菌，平均为2.82×10 CFU/mL。生理盐水组在降低活菌计数或LPS水平方面无效（P > 0.05）。与基线样本相比，aPDT组使活菌数减少了56.27%，aPDT + U使生物膜中的活菌数减少了56.97%。所有样本均检测到LPS，平均为18.84 EU/mL。生理盐水在降低LPS水平方面无效（P > 0.05）。aPDT在降低LPS水平方面有效（P < 0.05），平均为1.7 EU/mL。与aPDT组相比，aPDT + U促进了更多LPS的清除（P < 0.05），平均为0.02 EU/mL。对于CFU和LPS分析，aPDT和aPDT + U均比对照组更有效，而aPDT + U比aPDT更有效。总之，aPDT过程中超声激活光敏剂可增强对成熟多菌种生物膜的抗菌活性，同时降低LPS水平。
