Fabrication and in vitro evaluation of a novel calcium silicate scaffold with controlled architecture by rapid prototyping.

Abstract

Objective To fabricate porous calcium silicate（CS） scaffolds with controlled architecture by rapid prototyping and to evaluate the characterization of scaffolds and cell proliferation and differen- tiation on the prepared scaffolds. Methods The porous calcium silicate scaffolds with controlled architecture was fabricated by indirect rapid prototyping （RP-CS） which has the combined advantages of indirect solid freeform fabrication and gel-casting. Compared with the porous tricalcium phosphate scaffolds fabricated with the same method （RP-TCP）, the obtained RP-CS scaffolds were investigated by simulated body fluid （SBF） immersing test and in vitro incubation with bone marrow cells. Results An average compressive strength of 28 MPa for the RP-CS scaffold with the average total porosity of 71% was achieved. The scaffolds with mean channel diameter of about （555.82±29.77）μm have interconnected maeroporous architecture. The SBF test showed that hydroxyapatite could be found on the surface of RP-CS scaffold indicating its in vitro bioaetivity. The in vitro study showed that the rabbit bone marrow cells attached and proliferated on the surface of the RP-CS scaffolds. MTT tests demonstrated that the cell proliferation was significantly higher on RP-CS scaffolds than on RP-TCP scaffolds at 7 and 14 days （P〈0.05）. Moreover, the alkaline phosphatase （ALP） activities of cells on RP-CS scaffolds were increased as compared to the control at 7 days （P〈0.05）, indicating the capacity in promoting bone marrow cells differentiation into osteogenic ceils. Conclusion The obtained RP-CS scaffold in this study is biocompatible, and has promising future for bone tissue engineering. Key words: Silicates; Tissue engineering; Bone marrow cells; In vitro