Method: The tests were performed in 49 blocks of infected dentin with E. faecalis and treated with calcium hydroxide mixed with different vehicles (distilled water, 1% chlorhexidine solution, 1% chlorhexidine in propylene glycol, propylene glycol or pure extract guacatonga in propylene glycol), the dentin samples were incubated with the medicaments for a week. The efficiency of the pastes was assessed by using the live/dead technique and a confocal laser scanning microscopy. For comparison between the pastes, the Kruskal-wallis test with a level of significance set at 5% (p<0.05) was used.
Result: The calcium hydroxide paste associated with sterile distilled water showed the best performance (lower amount of live cells) and the calcium hydroxide associated to guacatonga extract propilenoglicolic did not present antimicrobial activity against E. faecalis.
Conclusion: It was concluded that no paste was fully effective on Enterococcus faecalis, being the Calcium hydroxide paste with distilled water the more effective.