title: Antimicrobial activity of different disinfection methods against biofilms in root canals.
abstract: OBJECTIVE
  The aim of the present study was to evaluate the bactericidal effects of different disinfection methods against microbial biofilms grown in root canals.
  
  
  METHODS
  A total of 300 freshly-extracted human teeth were infected with microbial pathogens. The biofilm formation and the effects of laser therapy, photodynamic therapy (PDT), iontophoresis, and disinfection with irrigating solutions were evaluated by counting the generations of microbial cells in the samples of root canals and by scanning electron microscopy.
  
  
  RESULTS
  Enterococcus faecalis and other Gram-positive cocci demonstrated highest sensitivity to the methods of antibacterial action compared here. In most of the cases observed, the antibacterial treatment was less effective against Gram-negative bacteria in dental biofilms. The biofilms that were most difficult to eliminate were those formed by Pseudomonas aeruginosa. Iontophoresis treatment with iodine and chemical disinfection with hypochlorite and chlorhexidine demonstrated the most powerful bactericidal effect. When PDT was applied with Fotosan as a photosensitizer, better disinfection was achieved in comparison to the other lasers alone.
  
  
  CONCLUSIONS
  The comparison of these different strategies for endodontic treatment showed that hypochlorite, followed by the chlorhexidine irrigant in our experimental conditions, gave the most satisfactory results against the formation of bacterial biofilms in the root canals.
authors: Department of Medical Microbiology, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria.
authors: Raina T
authors: RT
authors: Gergova
authors: Department of Conservative Dentistry, Faculty of Dental Medicine, Medical University of Sofia, Sofia, Bulgaria.
authors: Tzvetelina
authors: T
authors: Gueorgieva
authors: Department of Oral and Imaging Diagnostics, Faculty of Dental Medicine, Medical University of Sofia, Sofia, Bulgaria.
authors: Mariya S
authors: MS
authors: Dencheva-Garova
authors: Department of Oral and Imaging Diagnostics, Faculty of Dental Medicine, Medical University of Sofia, Sofia, Bulgaria.
authors: Assya Z
authors: AZ
authors: Krasteva-Panova
authors: Department of Conservative Dentistry, Faculty of Dental Medicine, Medical University of Sofia, Sofia, Bulgaria.
authors: Vasil
authors: V
authors: Kalchinov
authors: Department of Medical Microbiology, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria.
authors: Ivan
authors: I
authors: Mitov
authors: Department of Prosthetic Dentistry, Faculty of Dental Medicine, Medical University of Sofia, Sofia, Bulgaria.
authors: Julia
authors: J
authors: Kamenoff
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D018441:Biofilms / Q000187:drug effects; D002710:Chlorhexidine / Q000494:pharmacology; D003786:Dental Pulp Cavity / Q000187:drug effects / Q000382:microbiology*; D004203:Disinfection / Q000379:methods*; D006090:Gram-Negative Bacteria / Q000187:drug effects; D006095:Gram-Positive Cocci / Q000187:drug effects; D006801:Humans; D007478:Iontophoresis; D053685:Laser Therapy; D010778:Photochemotherapy; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D012388:Root Canal Irrigants / Q000494:pharmacology; D012973:Sodium Hypochlorite / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D012388:Root Canal Irrigants; D012973:Sodium Hypochlorite; D002710:Chlorhexidine
keywords: antimicrobial activity; biofilm; disinfection; endodontic infection; root canal