Comparison of the Antimicrobial Effect of Garlic Extract with two Intracanal Irrigants on Enterococcus Faecalis

It is very important to remove the microorganisms in the root canal before obturation. One of the causes of endodontic treatment failures is the existence of the bacteria responsible for resistant infections, including Enterococcus Faecalis. The aim of this study was to compare the antibacterial effect of the garlic extract with two intracanal irrigants on Enterococcus Faecalis. In this in-vitro study, the method of Well Agar Diffusion was used to compare the anti-bacterial effect of pure garlic extract (100%), garlic extract 80%, chlorhexidine 2%, sodium hypochlorite 5.25% and combined chlorhexidine 2% with pure garlic extract. Eighteen plates of Muller-Hinton agar were inoculated with E.faecalis. Each plate had 6 wells for test solutions and one of them was for sterile distilled water as the control. The prepared plates were distributed into aerobic (n=9) and anaerobic (n=9) groups, then incubated at 37°C for 24 hours. After that, the diameter of the zones of microbial inhibition around every well was measured and recorded. Data were analyzed using ANOVA and Tukey post-hoc tests. Our results demonstrated that Sodium hypochlorite 5.25% was more effective compared with the other antimicrobial materials in both aerobic and anaerobic groups. This difference was statistically significant (ANOVA, p<0.05). The most effective antimicrobial agents in aerobic and anaerobic conditions were in this order sodium hypochlorite (5.25%), chlorhexidine 2%, pure garlic extract, combined chlorhexidine 2% with pure garlic extract and garlic extract 80% respectively (p<0.05). However, the difference between pure garlic extract and combined chlorhexidine 2% with pure garlic extract in aerobic condition was not significant. The results showed that garlic extract is effective on Enterococcus Faecalis in both aerobic and anaerobic conditions; nevertheless it has less efficacy than chlorhexidine and sodium hypochlorite.