ABSTRACT
Elimination of root canal microorganisms is an important step in endodontic treatment. Each one of currently used medicaments has problems such as microbial resistance and tissue toxicity. Therefore, research is still needed to identify better alternatives. Propolis, as one of the honey bee products has been the focus of attention by many investigators in order to evaluate its biological properties. The aim of present study was to compare the activity of Calcium hydroxide and Propolis against lactobacillus, Enterococcus faecalis, Pepto-streptococcus and Candida albicans. This experimental study was conducted to evaluate antimicrobial activity of ethanol extract of Propolis and calcium hydroxide powder mixed with saline solution. Agar diffusion test and dilution methods were used to compare the results. There were separate plates to control diffusion of two substances in agar and antimicrobial activity of solvents. Figures about diameter of inhibition zone and minimal inhibitor concentration [MIC] and minimal bacterial concentration [MBC] were calculated using SPSS program. Paired T-test was used to compare the MIC experimental group differences. Propolis was more effective against Lactobacillus, Enterococcus Faecalis and Pepto-streptococcus with 8.6984mm compared with 7.0833mm mean diameter of inhibitory zone for Ca[OH]2. The difference was statistically significant [P<0.001] indicating that Ca[OH]2 was less effective against experimental microorganisms. The inhibitory zone of the two drugs demonstrated stronger effect of Propolis on contaminating microorganisms. On the other hand, the Minimal Inhibitory concentration of Propolis for all studied microorganisms was at least 4 times less than Calcium hydroxide. Propolis was more effective than calcium hydroxide against lactobacillus, Enterococcus faecalis and Pepto-streptococcus