In vitro evaluation of the antimicrobial effect of three endodontic sealers mixed with amoxicillin

The purpose of this in vitro study was to evaluate the antimicrobial effect of mixing amoxicillin with three different sealers when freshly mixed and set.

Using a direct contact test, Pulp Canal Sealer EWT (SybronEndo Corporation, Orange, CA), AH Plus (Dentsply International Inc, York, PA), and RealSeal SE (Pentron Clinical Technologies LLC, Wallingford, CT) were freshly mixed with amoxicillin and placed on the side wall of the microtiter plate. A 10-microL bacterial suspension of Enterococcus faecalis was placed directly onto the fresh sealers, and sealers set 1 day, 3 days, and 7 days after mixing. The bacteria were allowed to dry in direct contact with the sealer sample. Fresh media was then added, and growth of the bacteria was measured by spectrophotometry over an 8-hour period. One-way analysis of variance (ANOVA), two-way ANOVA, and Tukey multiple comparison were used for statistical significance.

All sealers mixed with amoxicillin showed complete inhibition of the growth of E. faecalis. Sealers mixed with amoxicillin had no statistical difference in inhibiting growth between freshly mixed samples and samples set for 1 day, 3 days, or 7 days (p > 0.05). Sealers without amoxicillin did not inhibit growth of E. faecalis, and no statistical difference was found between freshly mixed and set samples (p > 0.05). Sealers with amoxicillin were statistically different than sealers without amoxicillin when freshly mixed and set (p < 0.001).

Sealers mixed with amoxicillin inhibited the growth of E. faecalis significantly greater than sealers without amoxicillin (p < 0.001).