Aim: To assess and compare the antibacterial efficacy of methylene blue (MB) and red laser (660 nm) antimicrobial photodynamic therapy (aPDT), indocyanine green (ICG) and infrared laser (810 nm) aPDT, and dual-dye (MB and ICG) and dual light (red and infrared) aPDT on oral biofilms of Enterococcus faecalis (E. faecalis), Prevotella intermedia (P. intermedia), and Streptococcus mutans (S. mutans).
Materials and methods: Biofilms of E. faecalis, S. mutans, and P. intermedia were grown at 36°C and 5% CO2 for 7 days in a 96-well plate in a brain heart infusion (BHI) growth medium. Before aPDT, a total of 27 inoculums were collected from culture wells and grown on culture plates to assess baseline colony forming units (CFU). The microbial wells were treated with MBaPDT (group I), ICGaPDT (group II), and MBICGaPDT (group III). Post-aPDT, inoculums were collected from wells to be cultured to assess CFU. One-way analysis of variance (ANOVA) and student paired t-tests were used for statistical analysis. The significance level was fixed at p ≤ 0.05.
Results: Methylene blue antimicrobial photodynamic therapy (MBaPDT) caused a significant reduction in E. faecalis counts compared to other groups (f = 11.15, p = 0.01). aPDT on S. mutans resulted in a significant (p = 0.04) reduction of bacterial counts in the ICGaPDT group. aPDT on P. intermedia resulted in a significant reduction in bacterial counts (p ≤ 0.05) in MBaPDT and ICGaPDT groups.
Conclusion: Dual-dye and dual light aPDT showed an antibacterial effect against E. faecalis. It was ineffective against S. mutans and P. intermedia.
Clinical significance: Dual-dye aPDT may effectively reduce E. faecalis counts in infected root canals and improve the outcomes of root canal treatment.
Lopez-Jimenez L, Fuste E, Martinez-Garriga B, et al. Effects of photodynamic therapy on Enterococcus faecalis biofilms. Lasers in medical science 2015;30(5):1519–1526. DOI: 10.1007/s10103-015-1749-y
Alghamdi F, Shakir M. The Influence of Enterococcus faecalis as a dental root canal pathogen on endodontic treatment: a systematic review. Cureus 2020;12(3):e7257. DOI: 10.7759/cureus.7257
Albaghdadi SZ, Altaher JB, Drobiova H, et al. In vitro characterization of biofilm formation in prevotella species. Front Oral Health 2021;2:724194. DOI: 10.3389/froh.2021.724194
Krzyściak W, Jurczak A, Kościelniak D, et al. The virulence of Streptococcus mutans and the ability to form biofilms. Eur J Clin Microbiol Infect Dis 2014;33(4):499–515. DOI: 10.1007/s10096-013-1993-7
Chandrashekar Y, Yavagal PC, Soumya SV, et al. Efficacy of laser photodynamic therapy on fungal infections and post COVID mucormycosis: a narrative review. J Cardiovasc Dis Res 2021:12(3): 407–416.
Kofler B, Romani A, Pritz C, et al. Photodynamic effect of methylene blue and low level laser radiation in head and neck squamous cell carcinoma cell lines. Int J Mol Sci 2018;19(4):1107. DOI: 10.3390/ijms19041107
Nikinmaa S, Moilanen N, Sorsa T, et al. Indocyanine green-assisted and LED-light-activated antibacterial photodynamic therapy reduces dental plaque. Dent J (Basel) 2021;9(5):52. DOI: 10.3390/dj9050052
Beltes C, Economides N, Sakkas H, et al. Evaluation of antimicrobial photodynamic therapy using indocyanine green and near-infrared diode laser against Enterococcus faecalis in infected human root canals. Photomed Laser Surg 2017;35(5):264–269. DOI: 10.1089/pho.2016.4100
Akbari T, Pourhajibagher M, Chiniforush N, et al. Improve ICG based photodynamic properties through conjugation of ICG into nanographene oxide against Enterococcus faecalis. Avicenna J Clin Microb Infec 2018;5(1):64624. DOI: 10.5812/ajcmi.64624
Azizi A, Shohrati P, Goudarzi M, et al. Comparison of the effect of photodynamic therapy with curcumin and methylene blue on streptococcus mutans bacterial colonies. Photodiagnosis Photodyn Ther 2019;27:203–209. DOI: 10.1016/j.pdpdt.2019.06.002
Nemezio MA, de Souza Farias SS, Borsatto MC, et al. Effect of methylene blue-induced photodynamic therapy on a Streptococcus mutans biofilm model. Photodiagnosis Photodyn Ther 2017;20:234–237. DOI: 10.1016/j.pdpdt.2017.10.025
Liang X, Zou Z, Zou Z, et al. Effect of antibacterial photodynamic therapy on Streptococcus mutans plaque biofilm in vitro. J Innov Opt Health Sci 2020;13(6):2050022. DOI: 10.1142/S1793545820500224
Fimple JL, Fontana CR, Foschi F, et al. Photodynamic treatment of endodontic polymicrobial infection in vitro. J Endod 2008;34(6):728–734. DOI: 10.1016/j.joen.2008.03.011
Theodoro LH, Assem NZ, Longo M, et al. Treatment of periodontitis in smokers with multiple sessions of antimicrobial photodynamic therapy or systemic antibiotics: a randomized clinical trial. Photodiagnosis Photodyn Ther 2018;22:217–222. DOI: 10.1016/j.pdpdt.2018.04.003
Nie M, Deng DM, Wu Y, et al. Photodynamic inactivation mediated by methylene blue or chlorin e6 against Streptococcus mutans biofilm. Photodiagnosis Photodyn Ther 2020;31:101817. DOI: 10.1016/j.pdpdt.2020.101817
Hosseinzadeh R, Khorsandi K. Methylene blue, curcumin and ion pairing nanoparticles effects on photodynamic therapy of MDA-MB-231 breast cancer cell. Photodiagnosis Photodyn Ther 2017;18:284–294. DOI: 10.1016/j.pdpdt.2017.03.005
Shafirstein G, Bäumler W, Hennings LJ, et al. Indocyanine green enhanced near-infrared laser treatment of murine mammary carcinoma. Int J Cancer 2012;130(5):1208–1215. DOI: 10.1002/ijc.26126