Analysis of mineral trioxide aggregate surface when set in the presence of fetal bovine serum.

Understanding the chemical and physical characteristics of set mineral trioxide aggregate (MTA) surface can provide insight into its bioactivity. The purpose of this study was to describe the surface chemistry and morphology of gray and white MTA set in the presence of fetal bovine serum (FBS). Eight MTA blocks were prepared: four set in the presence of water and four in FBS. The surface morphologic characteristics were studied via scanning electron microscopy. The surface chemical composition of the set cement was investigated by energy dispersive x-ray spectroscopy and x-ray fluorescence. No difference was found between gray and white MTA when set in the same solution. However, MTA/FBS and MTA/water present differing surface morphology and chemical distributions. When set in FBS, MTA's surface had a homogenous distribution of chemicals and a relatively smooth globular appearance. MTA/water's surface was biphasic, containing large hexagonal crystalline plates composed of calcium embedded in a pool of globular crystals.