title: The efficacy of photodynamic and photothermal therapy on biofilm formation of Streptococcus mutans: An in vitro study.
abstract: BACKGROUND
  The alternative antibacterial treatments of photodynamic therapy (PDT) and photothermal therapy (PTT) significantly affect microbiota inactivation. The aim of the present research was the assessment of the antimicrobial and anti-biofilm effects of PDT with toluidine blue O (TBO) and PTT with indocyanine green (ICG) on Streptococcus mutans as a cariogenic bacterium.
  
  
  METHODS
  The S. mutans ATCC 35668 strain was treated with final concentrations of 0.1mg/mL TBO and 1mg/mL ICG with energy densities of 17.18 and 15.62J/cm2, respectively. Cell viability was evaluated after culturing and anti-biofilm potential was analyzed using crystal violet assay and scanning electron microscopy.
  
  
  RESULTS
  The number of S. mutans colony forming unit (CFU)/mL was significantly lower in the groups submitted to PDT (12.5-100μg/mL TBO) and PTT (62.5-1000μg/mL) compared to the control (untreated group). 0.1mg/mL TBO-PDT and 1mg/mL ICG-PTT showed stronger inhibitory effects on biofilm formation in S. mutans than other concentration levels, with a reduction of 63.87% and 67.3%, respectively.
  
  
  CONCLUSIONS
  Photo-elimination by high concentrations of TBO-PDT and ICG-PTT exhibited significantly stronger inhibitory effects on biofilm formation and cell viability in S. mutans.
authors: Department of Microbiology, School of Medicine, International Campus, Tehran University of Medical Sciences (IC-TUMS), Tehran, Iran.
authors: Leili
authors: L
authors: Beytollahi
authors: Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors: Maryam
authors: M
authors: Pourhajibagher
authors: Laser Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran.
authors: Nasim
authors: N
authors: Chiniforush
authors: Private Practice, Tehran, Iran.
authors: Roghayeh
authors: R
authors: Ghorbanzadeh
authors: Legal Medicine Research Center, Legal Medicine Organization, Tehran, Iran; Innovative Research Center, Islamic Azad University, Mashhad Branch, Mashhad, Iran.
authors: Reza
authors: R
authors: Raoofian
authors: Pediatrics Infectious Disease Research Center, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors: Babak
authors: B
authors: Pourakbari
authors: Department of Microbiology, School of Medicine, International Campus, Tehran University of Medical Sciences (IC-TUMS), Tehran, Iran; Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; Laser Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran; Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: abahador@sina.tums.ac.ir.
authors: Abbas
authors: A
authors: Bahador
mesh_terms: D018441:Biofilms / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007208:Indocyanine Green / Q000008:administration & dosage / Q000494:pharmacology; D054023:Lasers, Semiconductor; D010778:Photochemotherapy / Q000379:methods; D017319:Photosensitizing Agents / Q000008:administration & dosage / Q000494:pharmacology*; D010789:Phototherapy / Q000379:methods*; D013295:Streptococcus mutans / Q000187:drug effects*; D014048:Tolonium Chloride / Q000008:administration & dosage / Q000494:pharmacology
chemical_list: D017319:Photosensitizing Agents; D014048:Tolonium Chloride; D007208:Indocyanine Green
keywords: Biofilm; Cell viability; Indocyanine green; Photodynamic therapy; Photothermal therapy; Scanning electron microscopy; Streptococcus mutans; Toluidine blue O