The in vitro effect of antimicrobial photodynamic therapy with indocyanine green on Enterococcus faecalis: Influence of a washing vs non-washing procedure

• Published in: Photodiagnosis and photodynamic therapy Vol. 16; pp. 119 - 123
• Main Authors: Chiniforush, Nasim, Pourhajibagher, Maryam, Parker, Steven, Shahabi, Sima, Bahador, Abbas
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.12.2016
• Subjects: Bacterial Load - drug effects; Biofilm degradation; Biofilm development; Biofilm formation; Biofilms - drug effects; Biofilms - growth & development; Biofilms - radiation effects; Cell Survival - drug effects; Cell Survival - radiation effects; Disinfection - methods; Dose-Response Relationship, Drug; Dose-Response Relationship, Radiation; Endodontic infection; Enterococcus faecalis; Enterococcus faecalis - drug effects; Enterococcus faecalis - radiation effects; Hematology, Oncology and Palliative Medicine; Humans; Indocyanine green; Indocyanine Green - administration & dosage; Internal Medicine; Photochemotherapy - methods; Photosensitizing Agents - administration & dosage; Treatment Outcome; Enterococcus faecalis; Biofilm degradation; Indocyanine green; Biofilm formation; Endodontic infection; Biofilm development
• ISSN: 1572-1000; 1873-1597
• DOI: 10.1016/j.pdpdt.2016.09.007

•The concentration of indocyanine green (ICG) as photosensitizer (PS) has an important role in eradication of Enterococcus faecalis..•It’s recommended to apply ICG accompanied by laser irradiation without being washed out before irradiation.•The concentration of PS should be considered as a crucial point in antimicrobial photodynamic therapy. The purpose of this study was to evaluate the in vitro effect of washing and non-washing of indocyanine green (ICG) as photosensitizer (PS) on bacterial count, biofilm formation, development and degradation of Enterococcus faecalis. The anti-bacterial, anti-biofilm formation, anti-biofilm development and biofilm degradation of anti-microbial photodynamic therapy (aPDT) against E. faecalis was determined at concentrations of 3 to 2000μg/mL of ICG, subject to 18J/cm2 dose of diode laser (808nm) in washing and non-washing producers. Bacterial viability measurements and biofilm assays were evaluated by broth microdilution method and crystal violet assays, respectively. ICG-mediated aPDT, using 25 to 2000μg/mL and 50 to 2000μg/mL showed significant reduction in E. faecalis growth when compared to the control in non-washing and washing producers, respectively (P<0.05). Also, ICG-mediated aPDT showed a significantly inhibitory effect on biofilm formation of E. faecalis in concentration of 6 to 2000μg/mL and 100 to 2000μg/mL in non-washing and washing groups (P<0.05). The biofilm development was inhibited by concentrations of 12 to 2000μg/mL and 100 to 2000μg/mL in non-washing and washing groups. The biofilm degradation increased from concentrations of 12 to 2000μg/mL and 250 to 2000μg/mL in non-washing and washing groups, respectively. This study shows that the application of ICG should be accompanied by laser irradiation without being washed out to achieve better result for bacterial count reduction and anti-biofilm effects.