Preparation of calcium-phosphate cements with high compressive strength using meglumine as a water reducer

Calcium phosphate cements (CPCs) were prepared using meglumine to evaluate the effect of reduced mixing liquid in a CPC paste on plasticity and compressive strength. Raw CPC powders prepared using tetracalcium phosphate and dicalcium phosphate anhydrous were mixed with distilled water, meglumine aqueous solution (MG), and meglumine containing citric acid aqueous solution, to produce CPC pastes. Pastes prepared using MG exhibited a large plasticity, despite the fact that only a small amount of liquid was used for mixing the raw CPC powders (liquid-to-powder ratio of 0.21 g.g(-1)). The compressive strengths and bulk densities of the CPC setting bodies increased with increasing MG concentration in the mixing liquid. CPC setting bodies prepared using 3 mass% MG had a compressive strength greater than 80MPa after being soaked in simulated body fluid at 37 degrees C for 24 h. The high obtained compressive strength was attributed to a reduced amount of ( large) voids in the CPC setting body owing to efficient CPC powder dispersion in the mixing liquid during preparation of the CPC paste as a result of MG adsorbed onto the surface of the CPC powder. Although the setting time of CPC pastes prepared using MG was longer than that using distilled water because of the delay of hydroxyapatite formation with hydration, CPC pastes prepared using meglumine that contained citric acid aqueous solution had a shorter setting time. The resulting CPCs showed an improved performance for clinical application, that is, high compressive strength and adequate setting time. (C) 2016 The Ceramic Society of Japan. All rights reserved.