Chemical analysis composition of MTA Angelus gray, white and HP Repair through Electron Microscopy (SEM) coupled by Energy Dispersive Spectrometer (EDS)

Abstract Introduction Due to its biological and physicochemical properties, MTA has been indicated for different clinical situations in Endodontics. Objective The objective was to analyze the chemical composition of MTA Angelus white, gray and Repair HP cements. Material and method Five specimens of each type of cement studied were made, with 4mm diameter and 1mm height, using double-sided carbon conductive tape. Then, the samples were analyzed with the aid of a scanning electron microscope coupled to the dispersive energy spectrometry apparatus. They were later submitted to the Kolmogorov-Smirnov statistical test to verify normality. The chemical elements that presented normal distribution (average of 5%) were submitted to the ANOVA test and the Kruskal-Wallis test was applied to those with asymmetric distribution. Result After the analysis of the chemical elements, it was observed for the white MTA: O, Na, K, Mg, Al, Si, Ca and Bi; for gray MTA: O, Mg, Al, Si, Ca, Bi, Fe and S; and for HP Repair: O, Al, Mg, Si, Ca, Fe, Sr, C, Rb and W. 14 chemical elements were identified in the samples analyzed (O, Na, Al, Mg, Si, S, K, Ca (Fe, Sr, Bi, C, Rb and W). Of these, 5 were found in all cements studied: O, Al, Mg, Si and Ca. Conclusion The elements Rb, W and C were found only in Angelus' new MTA formulation, Repair HP. In the samples analyzed, Ca and O were the ones that presented the largest amount.