A comparative study of the E. faecalis antibiofilm efficacy of photoactivated curcumin, chlorophyll and riboflavin

Abstract

Background: Photosensitisers play a vital role for reactive oxygen species (ROS) production in diode laser 405 nm therapy. Curcumin, chlorophyll and riboflavin have been used and viewed in several studies as effective photosensitisers for the elimination of Enterococcus faecalis (E. faecalis), a persistent microorganism that may cause endodontic failure. While each has given valuable and promising results as an alternative endodontic irrigant, no study has compared the efficacy of these three natural dyes. Purpose: To prove that the photosensitiser curcumin in diode laser 405 nm therapy is more effective for E. faecalis biofilm degradation than chlorophyll and riboflavin, and that a duration of irradiation of 90 seconds is more effective than 60 seconds. Methods: The biofilm monospecies E. faecalis was divided into two microplates with 96-well according to the irradiation periods: 60 seconds (Group 1) and 90 seconds (Group 2). Each group contained one control (without a photosensitiser) and three treatments were carried out by adding the photosensitisers curcumin, chlorophyll and riboflavin, where each treatment contained eleven samples. After irradiation for 60 seconds and 90 seconds, a crystal violet assay was carried out for each group. Results: The one-way ANOVA test showed a significant difference between groups based on the irradiation period. Tukey’s test showed each treatment in each group also showed a significant difference (p<0.05) with curcumin as the best substance to cause biofilm degradation in both groups. The duration of the irradiation showed that the longer the biofilm was illuminated, the lower the absorbance value or optical density (OD). Conclusion: Curcumin irradiated for 90 seconds gives better biofilm degradation on E. faecalis due to its natural properties and molecular structure, highlighting its efficacy in photodynamic therapy

In Vitro Assessment of SWEEPS and Antimicrobial Photodynamic Therapy Alone or in Combination for Eradicating Enterococcus faecalis Biofilm in Root Canals

“…Nano-curcumin is less hydrophobic than curcumin, yet its antimicrobial effectiveness was similar to that of curcumin and slightly inferior to riboflavin [39]. In this study, we used the latest dental diode laser (BDL) to activate riboflavin, which has better antimicrobial performance compared to activation with an LED device [17][18][19]. The difference between riboflavin + BDL + SWEEPS group and NaOCl was not statistically significant (p = 0.990).…”

“…Nielsen et al utilized riboflavin in combination with an LED dental light-curing device. According to the outcomes of their research, the combination of riboflavin and LED did not demonstrate any impact on E. faecalis [17]. In contrast, other studies have shown that when riboflavin is activated using a diode laser, it exerts a notable inhibitory effect on E. faecalis [18,19].…”

“…The peak absorption wavelengths for riboflavin are 445 nm, 336 nm, and 270 nm [16]. Studies have also evaluated the antibacterial efficacy of aPDT using riboflavin [17][18][19]. Nielsen et al utilized riboflavin in combination with an LED dental light-curing device.…”

Riboflavin as a promising antimicrobial agent? A multi-perspective review

“…The disparity could be due to the interaction between different EPS production in mixed species biofilms ( Banerjee et al., 2020 ). In another study, the researchers observed an antibiofilm activity against biofilm produced by Enterococcus faecalis using riboflavin with 405nm diode laser ( Avianti et al., 2020 ). Overall, these studies highlight the potential of riboflavin as photosensitizer in aPDT against biofilm infections caused by various pathogens.…”

“…Firstly, the selection, binding and attachment efficiency of PS to the microbial cell surface, in particular cytoplasmic membrane needs to be carefully assessed. The architecture of cell surface structure varies among different microbes where different microbial cells will exhibit different levels of susceptibility to aPDT depending on the chemical structure of PS ( Avianti et al., 2020 ). For example, yeasts and Gram-positive bacteria are more vulnerable to anionic and neutral PS whilst Gram-negative bacteria are more resistant because of the existence of additional asymmetric outer membrane which are negatively charged.…”