Hydration behavior and radiopacity of strontium substituted Ca3SiO5 cement

Abstract

This study reports a facile method to synthesize the calcium silicate-based cement with an enhanced radiopacifying performance. Sr-substituted Ca3SiO5 (Ca3-xSrxSiO5, x=0.0 similar to 0.2) was prepared by solid-state reaction, and its phase, hydration behavior, and radiopacity were investigated and compared with those of 10 wt% Bi2O3-added Ca3SiO5. A nearly single-phase Ca3SiO5 was synthesized at 1400 degrees C and the solubility limit of Sr into Ca3SiO5 was approximately 3.3 mol % (x=0.1). The Sr substitution did not affect the size and morphology of Ca3SiO5 powder. The extent of hydration was slightly delayed in Sr-substituted Ca3SiO5, but the hydration products were the same composing of fiber-like calcium silicate hydrate (C-S-H) and plate-like calcium hydroxide (Ca(OH)(2)). The radiopacity of Ca3SiO5 was significantly enhanced with Sr substitution and it was slightly higher than that of Bi2O3-added Ca3SiO5 at a similar concentration. Consequently, Sr-substituted Ca3SiO5 can be a promising dental root canal filling material with an improved radiopacifying property.