Abstract

The main goal of endodontic therapy is to reverse the process of periapical periodontics by removing such microorganisms from the root canal. Sodium hypochlorite (NaOCl) as common endodontic irrigant, possess problems of toxicity, odor and discoloration of operatory items. An equally effective, but safe irrigant is desirable. The purpose of this study was to compare the anti-microbial activity of propolis with that of NaOCl (5.25%) in microbial flora of necrosed teeth with apical chronic periodontitis. Seventeen necrosed single canal teeth with apical chronic periodontitis were selected. After cavity preparation, two samples were taken of each canal with sterile paper points and were immediately transferred to the laboratory in BHI and thioglycollate broth intermediately. Then, serial dilution were made and inoculated on to aerobic and anaerobic plates in the presence or absence of NaOCl (5.25%) and propolis. After incubation, the colonies were counted and reported as CFU/ml. According to the results, the mean percentages of bacterial growth inhibition in the presence of NaOCl (5.25%) in aerobic and anaerobic conditions were 39.4 and 40.86%, respectively, while in the presence of propolis they were 29.42 and 46.4%, respectively. It is revealed that in anaerobic condition propolis was significantly more effective than aerobic condition. Also, in anaerobic condition, it is more effective than NaOCl, none significantly. In the case of NaOCl, it can be mentioned that, there is no significant difference in aerobic and anaerobic condition. It can be concluded that propolis and NaOCl have antimicrobial activity against aerobic and anaerobic bacteria and propolis has antimicrobial activity equal to that of NaOCl.

Key words: Antimicrobial, bacteria, propolis, sodium hypochlorite (NaOCl), root canal irrigants.