title: Enterococcus faecalis biofilms eradication by root canal irrigants.
abstract: The aim of this study was to evaluate the minimal biofilm eradication concentration (MBEC) of sodium hypochlorite (NaOCl), chlorhexidine (CHX), EDTA, and citric and phosphoric acids after 1, 5, and 10 minutes of exposure to biofilms of Enterococcus faecalis. The biofilms grew in the MBEC high-throughput device for 24 hours at 37 degrees C and were exposed to 10 serial two-fold dilutions of each irrigating solution. The viable cell counts were log(10) transformed, and a concentration of an irrigant was considered to eradicate the biofilms when it produced a reduction of > or = 5 logarithmic units. NaOCl was the most effective agent, capable of eradicating the biofilms after 1 minute at a concentration of 0.00625%. CHX eradicated biofilm after 5 minutes at 2%. EDTA and citric and phosphoric acid solutions were not effective against the biofilms at any concentration or time tested.
authors.affiliation: Department of Microbiology, School of Dentistry, University of Granada, Granada, Spain. mtarias@correo.ugr.es
authors.forename: María Teresa
authors.initials: MT
authors.lastname: Arias-Moliz
authors.forename: Carmen María
authors.initials: CM
authors.lastname: Ferrer-Luque
authors.forename: Miguel
authors.initials: M
authors.lastname: Espigares-García
authors.forename: Pilar
authors.initials: P
authors.lastname: Baca
mesh_terms: D000891:Anti-Infective Agents, Local / Q000008:administration & dosage / Q000494:pharmacology; D018441:Biofilms / Q000187:drug effects*; D002614:Chelating Agents / Q000008:administration & dosage / Q000494:pharmacology; D002710:Chlorhexidine / Q000008:administration & dosage / Q000494:pharmacology; D019343:Citric Acid / Q000008:administration & dosage / Q000494:pharmacology; D015169:Colony Count, Microbial; D004202:Disinfectants / Q000008:administration & dosage / Q000494:pharmacology; D004492:Edetic Acid / Q000008:administration & dosage / Q000494:pharmacology; D013293:Enterococcus faecalis / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D008826:Microbial Sensitivity Tests; D008855:Microscopy, Electron, Scanning; D010756:Phosphoric Acids / Q000008:administration & dosage / Q000494:pharmacology; D012388:Root Canal Irrigants / Q000008:administration & dosage / Q000494:pharmacology*; D012973:Sodium Hypochlorite / Q000008:administration & dosage / Q000494:pharmacology; D013696:Temperature; D013997:Time Factors
chemical_list: D000891:Anti-Infective Agents, Local; D002614:Chelating Agents; D004202:Disinfectants; D010756:Phosphoric Acids; D012388:Root Canal Irrigants; D019343:Citric Acid; D004492:Edetic Acid; D012973:Sodium Hypochlorite; C030242:phosphoric acid; D002710:Chlorhexidine