Antimicrobial Efficacy of Calcium and Sodium Hypochlorite at Different Concentrations on a Biofilm of and : An Comparative Study.

AIM

To compare the antimicrobial efficacy of sodium hypochlorite (NaClO at 2.5% and 5.25%) and calcium hypochlorite [Ca(ClO) at 2.5%] on a biofilm of ATCC 29212™ and ATCC 10231™.

MATERIALS AND METHODS

We performed an experimental study. Strains of and , which had previously been reactivated were used. Then the colonies to be used were standardized in a turbidity standard to guarantee a quantity of 108 (CFU/mL) using the McFarland scale (0.5). Subsequently, the biofilm formed in brain-heart infusion agar was seeded into 42 sterile disks previously embedded with the experimental substances. Both 2.5% NaClO and Ca(ClO) solutions were placed in each Petri dish. They were then incubated at 37°C for 24 hours and the inhibition halos were measured using the Kirby-Bauer technique.

RESULTS

The means between the halos corresponding to NaClO and Ca(ClO) at 2.5% were 13.38 ± 0.64 mm and 13.42 ± 0.62 mm, respectively. According to the Tukey test, no statistically significant differences were found between the hypochlorite groups evaluated ( = 0.989).

CONCLUSION

Both Ca(ClO) and NaClO have a similar antimicrobial efficacy with biofilm based on and , with no statistically significant differences between the two.

CLINICAL SIGNIFICANCE

This study demonstrates the effectiveness of Ca(ClO) and NaClO as endodontic irrigators to combat the most frequent microorganisms of the root canal.