comparison of antibacterial effects of three sealers used in endodontic treatments

Antibacterial effect of the sealers which are used in root canal therapy is a factor which increases the rate of success in root canal therapy. The aim of this study was to compare the antibacterial effect of three sealers (ZOE, AH26, Dorifill) on two bacterial species, staphylococcus aureuse and streptococcus mutans immediately after mixing and one week after mixing. Methods & Materials: For conducting this experimental study the bacteria were provided in isolated microbial species and a standard concentration from bacteria were cultured on the blood agar media with muller-Hinton base. The 5 millimeter diameter wells in the central area of the plate were punched. The fresh mixture of the mentioned sealer were put in the wells. The same process was performed on the sealers one week after mixing. After 24 hours incubation the diameters of the inhibitory zones in 4 directions were measured with boley - gauge. The results showed that the fresh mixture of AH26 for both bacterial species was significantly more effective than the others (P=0.001). One week after mixing for both species ZOE was significantly more effective than AH26 and AH 26 was significantly more effective than Dorifill (P=0.001). With regard to acceptable antibacterial effects of these three sealers performing studies about other properties of these sealers specially ZOE, is suggested.