Comparative Physicochemical and Biocompatible Properties of Radiopaque Dicalcium Silicate Cement and Mineral Trioxide Aggregate

Abstract 

Introduction

The purpose of this study was to comparatively examine physicochemical and biocompatible properties of 20 wt% bismuth oxide (Bi₂O₃)-containing dicalcium silicate cement and white-colored mineral trioxide aggregate (WMTA).

Methods

The radiopacity, setting time, diametral tensile strength, pH value, morphology, and phase composition of the cements with and without Bi₂O₃ were measured after mixing powders with water. Cement biocompatibility was evaluated by incubating the cement specimens with MG63 human osteoblast-like cells.

Results

The addition of Bi₂O₃ to the cement led to a significant increase (p < .05) in the setting time of 24 minutes. It was accompanied by a small decrease in the pH value but without adversely affecting diametral tensile strength. The radiopacity value of the Bi₂O₃-containing cement was equivalent to 7.3 mm of aluminum, which was significantly higher (p < 0.05) than pure cement without Bi₂O₃ (1.1 mm of aluminum) but lower (p < .05) than WMTA (9.3 mm of aluminum). However, it was greater than 3 mm of aluminum, which is the value recommended by ISO 6876/2001 standards. MG63 cell viability cultured on Bi₂O₃-containing cement was higher than that cultured on WMTA at all culture times.

Conclusions

The dicalcium silicate cement with 20 wt% Bi₂O₃ showed shortened setting time and good biocompatibility and thus may have the potential to be a root-end filling material alternative to MTA.

Key Words: Calcium silicate cement, mineral trioxide aggregate, radiopacifier, root-end filling material