In vitro comparison of anti-microbial activity of AH Plus, RSA and Ledermix against Enterococcus faecalis

Resumen

Aim: In vitro assessment of antimicrobial activity sustained by two root canal sealers: RSA®, AH Plus® as well as Ledermix® paste upon Enterococcus faecalis using three different techniques. Method: Direct contact test (DCT). Sealers were placed on an acrylic surface. A E. faecalis suspension was inoculated and left in a microtube with 1 mL of BHI broth. Logarithmic dilutions were conducted spreading them in blood agar plates so as to quantify CFU’s (colony forming units). Dilution test (DT). Sealers and paste were placed in a plastic cylinder. Bacteriae were inoculated in the culture broth and the same quantifi cation procedure was undertaken. Agar dilution test (ADT). On a blood agar plate three wells were manufactured: they were fi lled with both cements. On the Ledermix paste surface a E. faecalis suspension was inoculated so as to assess growth inhibition areas. Results: In the Direct contact test, Ledermix paste showed higher antimicrobial activity percentage. Neither of both cements nor the paste presented antimicrobial activity in dilution and Agar dilution test. In the Agar dilution test, AH Plus sealer and Ledermix paste exhibited a hemolysis halo in the blood agar plates. Conclusions: Direct contact test technique was considered the most appropriate to assess antimicrobial effects of cements.