Novel silicon-wollastonite based scaffolds for bone tissue engineering produced by selective laser melting

Abstract

Engineered bone tissue or scaffold is a potential alternative to the common use of bone grafts due to limitless supply and no disease transmission. We present a novel way to manufacture the highly efficient bioceramics combining osteoinductive and bioactive elements using additive manufacturing through selective laser melting without polymer based binder addition and post-processing sintering steps. A formulation of powder feedstock for the production of the scaffolds with an optimized geometry and a high strength is proposed. The structure with circular pores of 400 μm in diameter and porosity level of 35% exhibits density of around 1.4 g/cm3 and a compressive strength of 110 MPa, which is only slightly decreased after the immersion into Tris buffer for two weeks being of 90 MPa. The scaffolds demonstrate a high bioactivity and a controlled growth of the hydroxyapatite-like layer on the surface of the structures. The results of this work illustrate the ability for fabrication of complex-shaped ceramic based structures to be used as novel bone scaffolds and implants by SLM, and the promise for development of other ceramic – based materials using the proper precursor powders feedstock.