Comparison of disinfection of various concentrations of sodium hypochlorite and chlorhexidine on enterococcus faecalis contaminated resilone cones

Abstract

Resilon is a new poly caprolactone based obturation material which is similar to gutta percha in shape, texture and color. Even though Resilon cones are produced under aseptic condition. They can be contaminated by aerosols and physical sources during handling. Resilon cones cannot be disinfected by the conventional processes using moist or dry heat as this may alter their structures. Therefore a rapid chemical disinfection is needed. The purpose of this investigation was to compare efficiency of various concentrations of sodium hypochlorite (Naocl) and chlorhexidine (CHX) solutions on Enterococcus faecalis contaminated Resilone cones of 1-minute exposure. Materials and Methods: Resilon cones were randomly selected, were exposed by U.V for 4 hours, contaminated with Enterococcus faecalis (ATCC 29212) and were immersed in 5.25% Naocl, 2.5% Naocl, 1% Naocl, 0.5% Naocl , 2% CHX , 1% CHX and 0.5% CHX solutions for 1 minute. Then the cones were individually transferred to the test tubes, which contained 10 ml of thioglycollate media and were incubated at 37 C for 7 days. Positive and negative and washing controls were also used. Broth cultures were visually checked and subsequently blood cultures scorred by microbial growth. Results: Results indicate that all concentrations of sodium hypochlorite were effective in the rapid disinfection of all samplses of resilon cones. But none of the concentrations of chlorhexidine were not effective in 1- minute disinfection of Resilon cones. Conclusion: According to the results of the present study, 0.5% to 5.25% NaOCL solutions are effective agents for rapid disinfection of Resilone cones but not any of the CHX concentration would result in resilon cones disinfection.