Bacterial Contamination of Gutta-Percha Points From Different Brands and the Efficacy of a Chairside Disinfection Protocol

To evaluate the bacterial contamination of different brands of Gutta-Percha (GP) points routinely used in clinical practice and the efficacy of a chairside disinfection protocol with sodium hypochlorite. GP points (n=240), in sizes A, B, C, D, K15, K20, K25, K30, K35, K40, F1, F2, F3 (Dentsply®, Proclinic®, ProTaper® and R&S®), were randomly sampled from commercial packages already in use. These were added directly to Fluid Thioglycolate Medium (one GP point per tube) and incubated at 37ºC for 21 days. During this period, the presence/absence of turbidity was evaluated. To evaluate the efficacy of a chairside disinfection protocol, all detected contaminated GP points were immersed for 1 minute in 10 mL of 5.25% sodium hypochlorite, followed by 5 minutes in 10 mL of detergent solution (3% Tween 80 and 5% sodium thiosulfate) and a final rinse with 10 mL of sterile distilled water and incubated. The data was analysed using the chi-square test and differences between characteristics of dichotomic variables were performed using the binomial test. The significance level was set at P