3D printing of trabecular bone-mimetic structures by vat photopolymerization of bovine hydroxyapatite as a potential candidate for scaffolds

Author(s)

Erbereli, Rogerio ; de Camargo, Italo Leite ; Morais, Mateus Mota ; Fortulan, Carlos Alberto

• Document type: Journal article
• Source: Journal of the Brazilian Society of Mechanical Sciences and Engineering; v. 44, n. 5, p. 9-pg., 2022-05-01.

Abstract

The growing demand for bone-repairing applications has boosted the research for functional biomaterials, their processing and their conformation into bone scaffolds with controlled morphology and dimensions. However, it is still challenging and expensive to manufacture bioceramic scaffolds with complex morphology and tailored porosity. This paper presents the processing of low-cost hydroxyapatite from widely available bovine bones and the development of mimetic bone structures by vat photopolymerization additive manufacturing. First, bovine bones were processed to become reactive bioceramic hydroxyapatite through calcination and milling; a route called ceramization that eliminates any biological risk. Second, hydroxyapatite suspensions were developed with high solid loading (40 vol%), excellent stability (> 30 days) and low viscosity (< 200 mPa.s). Finally, a bovine trabecular bone was microCT scanned and replicated as mimetic bones through additive manufacturing vat photopolymerization using the obtained hydroxyapatite suspension. The printed scaffolds showed adequate mechanical resistance, similar to natural bone, verified by mechanical tests and finite element simulation. Conclusively, the presented methodology results in a promising combination of morphology, mechanical resistance and biocompatibility suited for bone scaffolds, using low-cost bovine-derived hydroxyapatite. Also, the described processing has a high potential for tissue engineering of customized/complex scaffolds for implants. (AU)

• FAPESP's process: 20/16012-1 - Fabrication of ceramic core plugs with multiscale porosity
• Grantee: Mateus Mota Morais
• Support Opportunities: Scholarships in Brazil - Doctorate