Fabrication of mesoporous calcium silicate/calcium phosphate cement scaffolds with high mechanical strength by freeform fabrication system with micro-droplet jetting

Abstract

In this study, we explored the feasibility of fabrication bioactive mesoporous calcium silicate/calcium phosphate cements (MCS/CPC) scaffolds with high mechanical strength by Freeform Fabrication System with Micro-Droplet Jetting. After preparation of ordered mesoporous calcium silicate (MCS) powder, ready-to-use MCS/CPC paste was formed by mixing calcium phosphate cement (CPC) powder and MCS powder with the binder polyvinyl alcohol (PVA) aqueous solution at a certain ratio of powder to liquid. MCS/CPC scaffolds with various architectures, pore sizes, and interconnectivity were then directly printed at room temperature using MCS/CPC paste. The mechanical strength, apatite formation, degradation rate, and cytocompatibility of the composite scaffolds were systematically investigated. The results showed that MCS/CPC paste exhibited outstanding printability to form MCS/CPC scaffolds. The hybrid MCS/CPC scaffolds with predefined pore size of 350 μm showed fast degradation rate, high mechanical strength, and good cytocompatibility. It was indicated that the hybrid MCS/CPC scaffolds might be a promising candidate for critical bone defect repair.