Effect of human, dentin, albumin and lipopolysaccharide on the antibacteerial activity of endodontic activity of endodontic irrigants.

CONTEXT

Human dentin powder (HD), bovine serum albumin (BSA) and endotoxin (LPS) may affect the antimicrobial activity of irrigating solutions.

AIM

To evaluate the inhibitory effect of HD powder, BSA, and LPS on the antibacterial activity of 0.5%, 1%, 2.5%, and 5% sodium hypochlorite (NaOCl), 2% chlorhexidine (CHX) gel, BioPure mixture of tetracycline, citric acid, and detergent (MTAD), and QMix.

METHODS

The direct contact test against (ATCC 29212) for 2-min, 30-min and 6-h was used. Sterile pyrogen-free water was the negative control. After experimental periods, a neutralizing agent was used. Colony-forming units were determined by 10-fold serial dilutions and culture on agar plates. Data were analyzed by Kruskal-Wallis and Dunn's test (α = 5%).

RESULTS

In the absence of inhibitors, all irrigants eliminated . In contact with HD, all solutions eliminated within 2-min, with the exception of MTAD. In the presence of BSA, only 5% NaOCl killed within 2-min. LPS did not affect the antibacterial effect of any irrigant. At 30-min and at 6-h, all substances eliminated .

CONCLUSIONS

In the presence of albumin, irrigants needed >2-min to eliminate , except for 5% NaOCl. The same was observed in the presence of dentin when was exposed to MTAD.