title: Efficacy of different concentrations of sodium hypochlorite and  chlorhexidine in disinfection of contaminated Resilon cones.
abstract: OBJECTIVE
  The aim of this study was to evaluate the effectiveness of different concentrations of Chlorhexidine (CHX) and sodium hypochlorite (NaOCl) in disinfecting contaminated Resilon cones within one minute.
  
  
  METHODS
  Fifty Resilon cones were divided into seven experimental groups and three control groups of 5 cones each. The cones of experimental groups were contaminated with E. faecalis and subsequently disinfected with different concentrations of NaOCl or CHX. The cones were then transferred into glass tubes containing thioglycollate media and incubated for 7 days. The tubes were examined for turbidity every 24 hours, and if bacterial growth occurred, samples were plated, incubated, gram stained and observed under microscope to confirm E. faecalis growth. Negative, positive, and washing control groups were also used.
  
  
  RESULTS
  All the positive and washing control showed profound E.faecalis growth. All the cones disinfected with CHX showed bacterial growth; however, no E. faecalis growth occurred in any samples disinfected with NaOCl.
  
  
  CONCLUSIONS
  Sodium hypochlorite, at concentrations of 0.5 to 5.25%, is an effective agent for disinfection of contaminated Resilon cones within one minute; however, chlorhexidine is unable to disinfect Resilon cones during one-minute exposure.
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Golgasht Street, Tabriz, Iran.
authors.forename: V
authors.initials: V
authors.lastname: Zand
authors.forename: A
authors.initials: A
authors.lastname: Salem-Milani
authors.forename: S
authors.initials: S
authors.lastname: Shahi
authors.forename: M-T
authors.initials: MT
authors.lastname: Akhi
authors.forename: S
authors.initials: S
authors.lastname: Vazifekhah
mesh_terms: D002710:Chlorhexidine / Q000008:administration & dosage*; D004203:Disinfection / Q000379:methods*; D004340:Drug Contamination; D013293:Enterococcus faecalis; D012387:Root Canal Filling Materials; D012973:Sodium Hypochlorite / Q000008:administration & dosage*
chemical_list: D012387:Root Canal Filling Materials; C486892:resilon sealer; D012973:Sodium Hypochlorite; D002710:Chlorhexidine