Maryam Pourhajibagher1, Nasim Chiniforush2, Reza Raoofian3, Babak Pourakbari4, Roghayeh Ghorbanzadeh5, Farzaneh Bazarjani6, Abbas Bahador7. 1. Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran. 2. Laser Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran. 3. Legal Medicine Research Center, Legal Medicine Organization, Tehran, Iran; Innovative Research Center, Islamic Azad University, Mashhad branch, Mashhad, Iran. 4. Pediatrics Infectious Disease Research Center, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. 5. Private practice, Tehran, Iran. 6. Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. 7. Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran; Laser Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: abahador@sina.tums.ac.ir.
Abstract
BACKGROUND: Eradication or suppression of microbial pathogens is a major goal in endodontic infection therapy. Sub-lethal doses of photo-activated disinfection (sPAD) as a new treatment method might be able to control the microorganisms involved in endodontic infections normally treated with PAD. This study evaluated the effect of sPAD using methylene blue (MB) in combination with diode laser irradiation on the growth and biofilm formation ability of Porphyromonas gingivalis as an endodontic pathogen. MATERIALS AND METHODS: The anti-microbial and anti-biofilm potential of sPAD against P. gingivalis were assessed at sub-lethal doses of MB and irradiation by diode laser on colony forming unit and crystal violet assays, respectively. RESULTS: MB-sPAD using 25μg/mL at a fluency of 117.18J/cm2 and 50-100μg/mL at a fluency of 93.75J/cm2 significantly P. gingivalis growth when compared to the control. MB at 100μg/mL at a fluency of 117.18J/cm2 in MB-mediated PAD showed a significant inhibitory effect on biofilm formation in P. gingivalis compared with MB-sPAD. CONCLUSION: High doses of MB-mediated sPAD exhibited anti-microbial and anti-biofilm potential activity, whereas lower doses of MB-mediated sPAD did not display this ability. Therefore, the dose of PAD used in vivo should be taken into account for endodontic treatment. Copyright Â
BACKGROUND: Eradication or suppression of microbial pathogens is a major goal in endodontic infection therapy. Sub-lethal doses of photo-activated disinfection (sPAD) as a new treatment method might be able to control the microorganisms involved in endodontic infections normally treated with PAD. This study evaluated the effect of sPAD using methylene blue (MB) in combination with diode laser irradiation on the growth and biofilm formation ability of Porphyromonas gingivalis as an endodontic pathogen. MATERIALS AND METHODS: The anti-microbial and anti-biofilm potential of sPAD against P. gingivalis were assessed at sub-lethal doses of MB and irradiation by diode laser on colony forming unit and crystal violet assays, respectively. RESULTS:MB-sPAD using 25μg/mL at a fluency of 117.18J/cm2 and 50-100μg/mL at a fluency of 93.75J/cm2 significantly P. gingivalis growth when compared to the control. MB at 100μg/mL at a fluency of 117.18J/cm2 in MB-mediated PAD showed a significant inhibitory effect on biofilm formation in P. gingivalis compared with MB-sPAD. CONCLUSION: High doses of MB-mediated sPAD exhibited anti-microbial and anti-biofilm potential activity, whereas lower doses of MB-mediated sPAD did not display this ability. Therefore, the dose of PAD used in vivo should be taken into account for endodontic treatment. Copyright Â