In vitro evaluation of the minimum bactericidal concentrations of different root-end filling materials.

AIM: The aim of this study was to evaluate the minimum bactericidal concentrations (MBC) of root-end filling materials ProRoot MTA, MTA Angelus and IRM. MATERIALS AND METHODS: Macrodilution broth method was used. Microorganisms used were: Staphylococcus aureus (ATCC 29213), Enterococcus faecalis (ATCC 29212) and Streptococcus mutans. Serial two-fold dilutions of root-end filling samples were prepared in macrodilution tubes with concentrations ranging from 1/2 to 1/512. The samples dilutions were incubated for 24 hours. After incubation, 0.1 ml of diluted culture was inoculated onto the surface of supplemented sheep blood agar (Merck, Germany) and all plates were incubated at 37°C in aerobic condition for 24 hours. The MBC was defined as the lowest concentration of root-end filling samples where no growth was recorded. RESULTS: MBC of both mineral trioxide aggregate (MTA) products against S. aureus were recorded as 15.62 mg/ml and for IRM 31.25 mg/ml MBC for both MTA groups against E. faecalis were recorded as 31.25 mg/ml and for IRM 62.5 mg/ml. MBC of all root-end filling samples against S. mutans were recorded as 62.5 mg/ml. CONCLUSION: All tested root-end filling materials showed acceptable MBC against S. aureus and E. faecalis. CLINICAL SIGNIFICANCE: All tested materials can be used safely for filling of a root-end cavity.