Neda Moslemi1, Nina Rouzmeh2, Fatemeh Shakerinia3, Abbas Bahador4, Pardis Soleimanzadeh Azar5, Mohammad Javad Kharazifard6, Mojgan Paknejad6, Reza Fekrazad7. 1. Laser Research Center of Dentistry, Dental Research Institute, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran. 2. Department of Periodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran. 3. Private Practice, Tehran, Iran. 4. Department of Microbiology, Tehran University of Medical Sciences, Tehran, Iran. 5. General Dentist, College Station, Texas, Iran. 6. Dental Research Center, Dental Research Institute, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran. 7. Department of Periodontics, Dental Faculty, AJA University of Medical Sciences, Tehran, Iran.
Abstract
Introduction:Porphyromonas gingivalis is one of the major pathogens in the development and progression of periodontal disease. Antimicrobial photodynamic therapy (aPDT) is a new approach which is sorted in non-invasive phototherapy for bacterial elimination. This in vitro study was conducted to compare photodynamic inactivation using Radachlorin and Toluidine blue O (TBO) as photosensitizers on P. gingivalis. Methods: Bacterial suspensions (200 µL) of P. gingivalis were exposed to either TBO with concentration of 0.1 mg/mL associated with portable light-emitting diode (LED) device (peak wavelength: 630 nm, output intensity: 2.000 mW/cm2, tip diameter: 6.2 mm) or 0.1% Radachlorin® and laser irradiation (InGaAlP, Peak wavelength: 662±0.1% nm, output power: 2.5 W, energy density: 6 J/cm2, fiber diameter: 2 mm). Those in control groups were subjected to laser irradiation or LED alone, Radachlorin® or TBO alone, and one group received neither photosensitizer nor light irradiation. Then counting of colony forming units (CFU) was performed to determine the bactericidal effects in each subgroup. Results: LED-based aPDT reduced the colony count of P. gingivalis more than that of TBO (P<0.001) or LED group (P=0.957). Also, laser-based aPDT had a great reduction in colony count of P. gingivalis in comparison with Radachlorin® (P<0.001) or laser irradiation alone (P=0.28). In addition, the colony count reduction of laser-based aPDT was significantly more than LED-based aPDT (P<0.05). Conclusion: Considering the results of this study, the viability of P. gingivalis was more affected by the combination of laser and Radachlorin® 0.1% in comparison with LED and TBO 0.1.
Introduction:Porphyromonas gingivalis is one of the major pathogens in the development and progression of periodontal disease. Antimicrobial photodynamic therapy (aPDT) is a new approach which is sorted in non-invasive phototherapy for bacterial elimination. This in vitro study was conducted to compare photodynamic inactivation using Radachlorin and Toluidine blue O (TBO) as photosensitizers on P. gingivalis. Methods: Bacterial suspensions (200 µL) of P. gingivalis were exposed to either TBO with concentration of 0.1 mg/mL associated with portable light-emitting diode (LED) device (peak wavelength: 630 nm, output intensity: 2.000 mW/cm2, tip diameter: 6.2 mm) or 0.1% Radachlorin® and laser irradiation (InGaAlP, Peak wavelength: 662±0.1% nm, output power: 2.5 W, energy density: 6 J/cm2, fiber diameter: 2 mm). Those in control groups were subjected to laser irradiation or LED alone, Radachlorin® or TBO alone, and one group received neither photosensitizer nor light irradiation. Then counting of colony forming units (CFU) was performed to determine the bactericidal effects in each subgroup. Results: LED-based aPDT reduced the colony count of P. gingivalis more than that of TBO (P<0.001) or LED group (P=0.957). Also, laser-based aPDT had a great reduction in colony count of P. gingivalis in comparison with Radachlorin® (P<0.001) or laser irradiation alone (P=0.28). In addition, the colony count reduction of laser-based aPDT was significantly more than LED-based aPDT (P<0.05). Conclusion: Considering the results of this study, the viability of P. gingivalis was more affected by the combination of laser and Radachlorin® 0.1% in comparison with LED and TBO 0.1.