Antibacterial action of calcium hydroxide vehicles and calcium hydroxide pastes

Aim: To evaluate the in vitro action of vehicles alone and with calcium hydroxide against different bacterial species. Methods: Agar plates were inoculated with the microbial suspensions, and wells were made and filled with the calcium hydroxide pastes and the vehicles used to prepare the pastes. The zones of inhibited bacterial growth were recorded, and the resulting measurements were statistically analyzed. Results: Enterococcus faecalis was the most resistant microorganism to all medicaments. Calcium hydroxide + p-monochlorophenol; calcium hydroxide + p-monochlorophenol- propylene glycol pastes; and p-monochlorophenol, p-monochlorophenol- propylene glycol, and chlorhexidine gluconate gel alone showed the largest zones of inhibition against all the tested microorganisms. Conclusions: The vehicle used to prepare the calcium hydroxide paste might contribute to its antibacterial action. Chlorhexidine gluconate gel used alone, and camphorated p-monochlorophenol and camphorated p-monochlorophenol- propylene glycol as vehicles of calcium hydroxide, could be recommended, in an antimicrobial sense.