Influence of antimicrobial photodynamic therapy with different pre-irradiation times on children’s dental biofilm: randomized clinical trial

• Published in: European archives of paediatric dentistry Vol. 23; no. 6; pp. 897 - 904
• Main Authors: Lima, N. G., Monteiro, R. M., Torres, C. P., de Souza-Gabriel, A. E., Watanabe, E., Borsatto, M. C.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-12-2022; Springer Nature B.V
• Subjects: Anti-Infective Agents; Antimicrobial agents; Bacteria; Biofilms; Biofilms - radiation effects; Child; Clinical trials; Colonies; Dentistry; Humans; Humidity; Irradiation; Lasers; Medicine; Methylene blue; Methylene Blue - therapeutic use; Microorganisms; Original Scientific Article; Pediatrics; Photochemotherapy - methods; Photodynamic therapy; Photosensitizing Agents - therapeutic use; Sample size; Semiconductor lasers; Statistical analysis; Variance analysis; Clinical trial; Photodynamic therapy; Dental biofilm; Children
• ISSN: 1818-6300; 1996-9805
• DOI: 10.1007/s40368-022-00716-8

Purpose
Photodynamic therapy (PDT) is effective in reducing pathogenic microorganisms in the oral cavity and in preventing dental diseases. This study evaluated the pre-irradiation time using PDT (diode laser associated with 0.01% methylene blue) to decrease the number of microorganisms in the visible plaque in permanent teeth.
Methods
This randomized clinical trial included 108 homologous lower permanent first molars (36 and 46) with biofilm from 54 children aged six to 12 years. PDT was performed (0.01% methylene blue photosensitizer/therapeutic laser-InGaAIP), according to the following protocols: Group 1, biofilm collection of the distal area of the lingual surface of 36 µm before PDT; group 2, mesial area of the lingual surface of 36 µm 1 min after PDT; group 3, area of the lingual surface of 46 µm before PDT; and group 4, mesial area of the lingual surface of 46 µm 5 min after PDT.
Results
After statistical analysis, significant differences were observed between the groups (
p
 = 0.000). In groups 2 and 4, the number of bacteria tended to decrease, with a more evident bacterial reduction in group 4.
Conclusions
Pre-irradiation reduced the number of colony-forming units of mature bacterial biofilms in vivo. A time of 5 min resulted in a greater reduction in the number of colony-forming units.
Clinical trial registration
ReBEC Identifier: RBR-6bqfp3; Date of Register: March 2nd, 2020. Retrospectively Registered.