Preparation, mechanical property and cytocompatibility of freeze-cast porous calcium phosphate ceramics reinforced by phosphate-based glass

In this study, phosphate-based glass (PG) was used as a sintering aid for freeze-cast porous biphasic calcium phosphate (BCP) ceramic, which was sintered under a lower temperature (1000 degrees C). The phase composition, pore structure, compressive strength, and cytocompatibility of calcium phosphate composite ceramics (PG-BCP) were evaluated. The results indicated that PG additive reacted with calcium phosphate during the sintering process, forming p-Ca2P2O7; the ions of sodium and magnesium from PG partially substituted the calcium sites of beta-calcium phosphate in BCP. The PG-BCP showed good cytocompatibility. The pore width of the porous PG-BCP ceramics was around 50 mu m, regardless of the amount of PG sintering aid. As the content of PG increased from 0 wt% to 15 wt.%, the compressive strength of PG-BCP increased from 0.02 MP to 0.28 MPa. When the PG additive was 17.5 wt.%, the compressive strength of PG-BCP dramatically increased to 5.66 MPa. Addition of 15 wt.% PG was the critical point for the properties of PG-BCP. PG is considered as an effective sintering aid for freeze-cast porous bioceramics. (C) 2016 Elsevier B.V. All rights reserved.