Disinfection of gutta-percha cones with chlorhexidine and sodium hypochlorite.

OBJECTIVES To evaluate the effectiveness of chlorhexidine (CHX) or sodium hypochlorite (NaOCl) in disinfecting gutta-percha cones, to verify contamination of gutta-percha cones in their boxes, and to identify microorganisms after intentional contamination by handling cones. STUDY DESIGN Gutta-percha cones contaminated in vitro with several microorganisms were left in contact with tested disinfecting solutions for different times, sterility of storage boxes was evaluated by immersing cones in broth medium, and the microorganisms most frequently found in handling cones were identified using biochemical tests. RESULTS CHX was not effective in eliminating Bacillus subtilis spores on gutta-percha cones after 72 h of contact with the disinfecting substance. 5.25% NaOCl eliminated spores from gutta-percha after 1 min of disinfection. The cones evaluated from their boxes did not show contamination in 94.5% of the cases. The microbial genus most frequently found after intentional contamination with gloves was Staphylococcus. CONCLUSION 5.25% NaOCl is an effective agent for a rapid disinfection of gutta-percha cones.