Effect of white mineral trioxide aggregate mixed with disodium hydrogen phosphate on inflammatory cells

The aim of this study was subjective evaluation of inflammatory cells subsequent to subcutaneous implantation of white mineral trioxide aggregate (WMTA) mixed with disodium hydrogen phosphate (Na(2)HPO(4)) in rats.

Forty Wistar rats were used in this study. Polyethylene tubes filled with WMTA mixed with Na(2)HPO(4) and WMTA alone and also empty tubes serving as control were implanted into subcutaneous tissue and harvested after 7, 15, 30, and 90 days. Histologic sections were stained with hematoxylin-eosin and observed under a light microscope. Inflammatory reactions were categorized as 0 or none (without inflammatory cells), 1 or mild (inflammatory cells < 25), 2 or moderate (25-125 inflammatory cells), and 3 or severe (more than 125 inflammatory cells). Statistical analyses were performed with the Kruskal-Wallis and Mann-Whitney tests.

WMTA alone provoked a moderate inflammatory reaction after 7 and 15 days, which significantly differed from WMTA mixed with Na(2)HPO(4) and the control group, which provoked a mild inflammatory reaction (P < .05). However, there were no significant differences at any period beyond 30 days.

This study indicates that adding Na(2)HPO(4) to WMTA creates a more biocompatible material than WMTA alone.