Making foam-like bioactive glass scaffolds by vat photopolymerization

Abstract

This study explores the feasibility of bioactive glass scaffolds by using a stereolithographic technology (digital light processing-based vat photopolymerization) as fabrication method and the micro-tomographic reconstruction of an open-cell polymeric sponge as input virtual model to the printing system, in the attempt to replicate the trabecular architecture of cancellous bone. Additively-manufactured scaffolds were investigated from morphological (scanning electron microscopy), microstructural (X-ray diffraction), mechanical (compressive tests) and bioactive viewpoints (immersion studies in simulated body fluid (SBF)). Well-densified foam-like glass scaffolds were obtained after sintering, provided with suitable mechanical properties (compressive strength 21.9 ± 6.2 MPa, elastic modulus 4.8 ± 0.1 GPa, Weibull modulus 3.9) for bone-contact applications. The formation of a hydroxyapatite layer on scaffold struts after soaking in SBF also demonstrated the in vitro bioactivity of the printed structures.

Keywords

• Bioactive glass
• Additive manufacturing
• Stereolithography
• Scaffold
• Biomaterials