Evaluation of the antifungal effects of mineral trioxide aggregate materials.

The aim of this study was to evaluate and compare the antifungal effect of white-coloured mineral trioxide aggregate (WMTA) and grey mineral trioxide aggregate (GMTA) using a tube-dilution test. MTA preparations were freshly mixed and tested after 24 h on Candida albicans. The experiment was carried out in 24-well culture plates. Fifty wells were used and divided into four experimental groups (freshly mixed WMTA, freshly mixed GMTA, 24 h-set WMTA and 24 h-set GMTA) of 10 wells each and control groups of five wells each. Plates of Sabouraud dextrose agar mixed with C. albicans served as positive control, and Sabouraud dextrose agar without C. albicans served as negative control. Fresh inoculate of C. albicans was prepared by growing an overnight culture from a stock culture. Aliquots of C. albicans were then taken from the stock culture and plated on the agar compound of the experimental and control groups. All plates were incubated at 37 degrees C for 1, 24 and 72 h. Growth of fungi was monitored daily by the presence of turbidity. Results showed that in the freshly mixed as well as 24 h-set MTA cements fungal growth was observed during 1-h incubation, whereas by increasing the incubation time, no fungal growth was observed in 24 and 72 h. It was concluded that MTA cements (freshly mixed and 24-h set) were effective against C. albicans.