In vitro study of antimicrobial activity of irrigating solutions in the elimination of Enterococcus faecalis

Facultative bacteria such as Enterococcus faecalis, have been isolatedfrom pathologically involved root canals, being considered one of themost resistant species in the oral cavity one of the possible causes of failure of root canal treatment. The aim of this study was to assess, in vitro, the effectiveness of the several irrigating solutions in the elimination of Enterococcus faecalis. The disk-diffusion in agar test was utilized in this study. The bacteria utilized was Enterococcus faecalis ATCC 29212 and the irrigating solutions were NaOCl 0,5%, 1%, 2,5% and 5%; chlorhexidine 0,12% and 2%; EDTA 17% and H2O2 10 vol Chlorhexidine 2% and NaOCl 5% were the most effective irrigators and NaOCl 0,5%; EDTA 17% and H2O2 showed ineffectiveness in the elimination of this specie. These results suggest that the elimination of E. faecalis depends on the concentration and type of irrigator used.