Effect of calcium hydroxide and chlorhexidine against Enterococcus faecalis

AIM: To evaluate the efficacy of calcium hydroxide(Ca(OH)2) and chlorhexidine gel on the elimination of intratubular Enterococcus faecalis.METHODS: Sixty single-root teeth were infected with E.faecalis.The infected teeth were randomly divide into four groups,with 15 teeth in each group.The teeth were then treated with Ca(OH)2,20g/L chlorhexidine gel,Ca(OH)2 plus 20g/L chlorhexidine gel,or saline(0.9% NaCl) as a negative control.Dentin samples at the depth of 0 to 100 mm and 100 to 200 mm from these root canal preparations were collected by GG drilling.The collected dentin was diluted by ten-fold gradient and plated on BHI agar plates.After 24 hours,CFU was counted to compare the bacterial survival.RESULTS: A significant decrease in the number of CFUs of viable E.faecalis was observed after treatment with three experimental groups when compared with the control group,and a significantly statistical difference was found between the experimental groups and control group(P0.05).Chlorhexidine gel had a significantly higher antimicrobial efficacy as measured by the number of CFUs of viable cells than Ca(OH)2.No difference was observed between the antimicrobial properties of chlorhexidine gel with and without the addition of Ca(OH)2(P0.05).CONCLUSION: Both Ca(OH)2 and chlorhexidine have antimicrobial effects on E.faecalis.Chlorhexidine gel has increased antimicrobial activity when compared with Ca(OH)2.