Comparative evaluation of 2% chlorhexidine , 0.2% cetrimide and 5% minocycline against E.faecalis : An in vitro study

Background: High prevalence of E.faecalis in root canal treated teeth with post-treatment disease suggests that this organism may be a key player in endodontic failure. Irrigants have a major role eradicating them from the complex root canal system. Objectives: were to evaluate and to compare 2% chlorhexidine, 0.2% cetrimide and 5% minocycline by measuring the width of zone of inhibition of E. Faecalis Methodology: The antimicrobial activity of E. faecalis (ATCC 29212) was carried on sheep blood agar in nutrient broth. A total of 60 wells were made, 20 for each group and 50 µl of the test irrigant solution pipetted into each well. The test irrigants were 2% chlorhexidine, 0.2% cetrimide , 5% minocycline. The agar plates were carefully placed in CO2 incubator at 37 °c for 48 hours. Zone of inhibition were measured using mm scale Statistical analysis was done using SPSS (version 17.0) software. ANOVA Test and Tukeys HSD tests were used to evaluate the mean and inter group comparison between the various groups. The p value was set at ?0.05. Results: Among the experimental solutions 5% minocycline showed the largest zone of inhibition followed by chlorhexidine and cetrimide with statistical significant difference between all the groups, with p value <0.05. Conclusion: The present study concludes 5% minocycline is the best choice of irrigant when compared to 2% chlorhexidine and 0.2% cetrimide to eradicate E.faecalis in failed root canal cases.