Disinfection efficiency of irreversible hydrocolloid impressions using different concentrations of sodium hypochlorite: a pilot study.

AIM Dental impressions are potential sources of bacterial contamination which could eventually lead to transmissible infectious diseases through the blood or saliva. Sodium hypochlorite is an effective disinfectant recommended by the American Dental Association (ADA) in a 1:10 dilution for a ten minute immersion to disinfect irreversible hydrocolloid impressions. As the ADA protocol is sometimes neglected in busy practice settings, this pilot study was designed to determine an efficient and effective protocol for disinfection of irreversible hydrocolloid impressions. METHODS AND MATERIALS Various concentrations of sodium hypochlorite and disinfection times were challenged against irreversible hydrocolloid impressions contaminated with six Gram-positive and Gram-negative bacteria. RESULTS A two minute immersion time in a 0.6% solution of sodium hypochlorite protocol was found to prevent bacterial growth on the impressions. CONCLUSION Disinfection of irreversible hydrocolloid impressions in a 0.6% solution of sodium hypochlorite for two minutes was as effective as the ADA's protocol of using a 0.5% sodium hypochlorite solution for ten minutes to destroy the test bacteria.