Evaluation Of Antimicrobial Efficacy of Photosensitizer Loaded with Various Nanoparticles Mediated Photo Dynamic Therapy - An In Vitro Study
Keywords: Photodynamic therapy, Toluidine blue O, Enterococcus faecalis, Diode laser, Nanoparticles, Chitosan nanoparticles,Silver nanoparticles, Root canal disinfection
AuthorsABSTRACTAim: To evaluate the antimicrobial efficacy of toluidine blue O (TBO)mediated photodynamic therapy (PDT) combined with various nanoparticle carriers in comparison with sodium hypochlorite (NaOCl) for disinfecting root canals infected with Enterococcus faecalis. Materials and Methods: One hundred freshly extracted single-rooted human teeth were decoronated and standardized to a root length of 13 mm. Following biomechanical preparation using rotary instrumentation, the samples were sterilized and inoculated with E. faecalis. Specimens were incubated at 37°C for 21 days to allow biofilm formation. The samples were randomly allocated into five groups (n=20): Group 1 - 5.25% NaOCl , Group 2 - TBO + diode laser (DL); Group 3 - Chitosan-TBO nanoparticles (Chit-TBO NPs) + DL; Group 4 - Silver-TBO nanoparticles (Ag-TBO NPs) + DL; and Group 5 TBO-Chitosan-Gold-Silver nanoparticles (TBO-Chit-Au-Ag NPs) + DL. Antimicrobial efficacy was assessed using colony-forming unit (CFU) counts. Statistical analysis was performed using the Shapiro–Wilk test for normality and the Tukey post hoc test for group comparisons, with the significance level set at p < 0.05. Results: Group 1 demonstrated the lowest mean CFU count, indicating superior antimicrobial efficacy, while Group 2 exhibited the highest CFU values. All nanoparticle-mediated PDT groups (Groups 3–5) showed significantly reduced CFU counts compared to TBO alone (p<0.0001). Among them, the Ag-TBO NP group demonstrated the lowest bacterial counts; however, no statistically significant differences were observed among the nanoparticle groups (p>0.05). Conclusion: NaOCl remains the most effective irrigant for root canal disinfection. Nanoparticle-assisted PDT significantly enhances antimicrobial efficacy compared to TBO alone and shows potential as an adjunctive approach, although it does not surpass NaOCl under the conditions of this study.
INTRODUCTIONThe main etiologic agents that play a significant role in the pathogenesis of pulp and periapical diseases are microorganisms and their metabolic waste, which extensively influence the outcome of endodontic treatment [1]. Effective root canal treatment (RCT) is essential in the achievement of the elimination of microbes in the root canal system. Nevertheless, even with the development of chemo-mechanical preparation, irrigation treatment, intracanal medicaments, and hermetic obturation, the canal disinfection is still a clinical problem [2]. Primary endodontic infections normally comprise a polymicrobial flora that is predominantly composed of gram-negative non-aerobic bacteria. Persistent or secondary infections, on the other hand, are mainly caused by gram-positive organisms and especially by Enterococcus faecalis (E. faecalis) [3]. E. •••••••••••••••••••••••••••••••• ejprd.org - Published by Riset Publishing Services LLC.
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