ANTIBACTERIAL ACTIVITY OF MINERAL TRIOXIDE AGGREGATE, NEW ENDODONTIC CEMENT, RETRO MTA AND ORTHO MTA AGAINST COMMON ENDODONTIC PATHOGENS

Abstract: Introduction: Mineral trioxide aggregate [MTA] has extensive applications in endodontic treatment. Retro MTA, Ortho MTA and new endodontic cement [NEC] were also introduced to overcome the limitations of MTA. This study sought to compare the antibacterial activity of MTA, NEC, Ortho MTA and Retro MTA against common endodontic pathogens. Materials and Methods: This in vitro, experimental study was conducted on standard strains of Streptococcus mutans, Enterococcus faecalis, Actinomyces viscosus and Escherichia coli. Antibacterial activity of the materials was tested using the disc diffusion method. Wells were created in Mueller Hinton agar plates inoculated with bacterial suspensions with 0.5McFarland concentration. The plates were incubated at 35°C for 18 hours and diameter of the growth inhibition zones was measured by a ruler. The data were analyzed using the Kruskal Wallis test. Pairwise comparisons were done using Bonferroni test. Results: The mean diameter of the growth inhibition zone of E. coli was 2.916, 10.833, 10.333 and 7.25mmin presence of MTA, NEC, Retro MTA and Ortho MTA, respectively [P<0.05]; these values were 5.083, 8.916, 7.916 and 7.416mm, respectively for E. faecalis [P=0.17], 6.0, 8.916, 7.333 and 8.333mm, respectively for S. mutans [P<0.24] and 1.916, 8.083, 0 and 0.666, respectively for A. viscosus [P<0.05]. Antibacterial activity of all four materials was the same against E. faecalis and S. mutans. All materials showed limited antibacterial activity against A. viscosus except for NEC. Conclusion: Retro MTA and Ortho MTA had acceptable antimicrobial activity against common endodontic pathogens [except for A. viscous] and thus, they can be used as an alterative to MTA in the clinical setting given that their other properties are confirmed to be optimal. Key words: Anti-Bacterial Agents; Mineral Trioxide Aggregate; Root Canal Therapy