Abdollah Ghorbanzadeh1, Abbas Bahador2, Pegah Sarraf1, Roya Ayar3, Reza Fekrazad4, Sohrab Asefi5. 1. Endodontic Department, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran. 2. Microbiology Department, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. 3. Private Practice, Iran. 4. Department of Periodontology, Dental Faculty-Laser Research Center in Medical Sciences, AJA University of Medical Sciences, Tehran, Iran; International Network for Photo Medicine and Photo Dynamic Therapy (INPMPDT), Universal Scientific Education and Research Network (USERN), Tehran, Iran. Electronic address: rezafekrazad@gmail.com. 5. Department of Orthodontics, Dental School, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: sohrabasefi67@gmail.com.
Abstract
BACKGROUND AND OBJECTIVES: Intracanal disinfection plays an important role in endodontic treatment success. Enterococcus faecalis (E. faecalis) is a resistant microorganism responsible for endodontic infections. We aimed to assess the bactericidal effects of three disinfection methods on E. faecalis biofilm. MATERIALS AND METHODS: Fifty-five freshly extracted single-rooted human teeth were evaluated. A barbed broach was used to extract the pulp tissue. No further root canal preparation was performed. Specimens were sterilized with gamma radiation, and inoculated with E. faecalis suspension. They were then incubated for 4 days and 4 weeks. Biofilm formation was confirmed using a scanning electron microscope (SEM). The teeth were randomly assigned to three subgroups (n = 7) to assess the antimicrobial efficacy of the following three disinfection methods against immature (4-day) and mature (4-week) biofilms: the conventional chemomechanical debridement (CCMD), CCMD + light-activated disinfection (LAD; 810 nm, 0.3 W, 120 J/cm2) with indocyanine Green (EmunDo) as photosensitizer and CCMD + diode laser irradiation (810 nm, 2 W). The teeth were then longitudinally split into two halves and the colony count was reported as colony forming units (CFUs) to assess bacterial viability after each disinfection protocol. RESULTS: None of the disinfection methods could completely remove the biofilm. CCMD + LAD caused the highest and CCMD + diode laser caused the lowest reduction in biofilm. Antibacterial efficacy was significantly lower against the mature (4-week) biofilm compared with immature (4-day) biofilm in all groups (P < 0.05). CONCLUSION: All three disinfection methods were effective for partial elimination of E. faecalis biofilm. But CCMD + LAD was significantly more efficacious in decreasing both mature and immature biofilms.
BACKGROUND AND OBJECTIVES: Intracanal disinfection plays an important role in endodontic treatment success. Enterococcus faecalis (E. faecalis) is a resistant microorganism responsible for endodontic infections. We aimed to assess the bactericidal effects of three disinfection methods on E. faecalis biofilm. MATERIALS AND METHODS: Fifty-five freshly extracted single-rooted human teeth were evaluated. A barbed broach was used to extract the pulp tissue. No further root canal preparation was performed. Specimens were sterilized with gamma radiation, and inoculated with E. faecalis suspension. They were then incubated for 4 days and 4 weeks. Biofilm formation was confirmed using a scanning electron microscope (SEM). The teeth were randomly assigned to three subgroups (n = 7) to assess the antimicrobial efficacy of the following three disinfection methods against immature (4-day) and mature (4-week) biofilms: the conventional chemomechanical debridement (CCMD), CCMD + light-activated disinfection (LAD; 810 nm, 0.3 W, 120 J/cm2) with indocyanine Green (EmunDo) as photosensitizer and CCMD + diode laser irradiation (810 nm, 2 W). The teeth were then longitudinally split into two halves and the colony count was reported as colony forming units (CFUs) to assess bacterial viability after each disinfection protocol. RESULTS: None of the disinfection methods could completely remove the biofilm. CCMD + LAD caused the highest and CCMD + diode laser caused the lowest reduction in biofilm. Antibacterial efficacy was significantly lower against the mature (4-week) biofilm compared with immature (4-day) biofilm in all groups (P < 0.05). CONCLUSION: All three disinfection methods were effective for partial elimination of E. faecalis biofilm. But CCMD + LAD was significantly more efficacious in decreasing both mature and immature biofilms.