3-D high-strength glass-ceramic scaffolds containing fluoroapatite for load-bearing bone portions replacement

This study aimed to fabricate and investigate the structure, mechanical properties and bioactivity of three-dimensional (3-D) glass-ceramic scaffolds for bone tissue engineering. The scaffold material was a fluoroapatite-containing glass-ceramic synthesized by a melting-quenching route. Glass-ceramic powders were mixed with polyethylene particles acting as pore formers; the blend was pressed to obtain "green" compacts that were thermally treated to remove the organic phase and to sinter the inorganic one. The structure and morphology of the resulting scaffolds were characterized by X-ray diffraction, scanning electron microscopy, density measurements and capillarity tests. Crushing tests were carried out to investigate the mechanical properties of the scaffolds. The in vitro bioactivity was assessed by soaking the scaffolds in simulated body fluid for different time frames and by analyzing the modifications that occurred on the sample surface. The scaffolds had an interconnected macroporous structure with pores up to 50% vol. and they showed an orthotropic mechanical behaviour and strength well above 20 MPa. In addition, in vitro tests put into evidence the excellent bioactivity of the material. Therefore, the prepared scaffolds can be used in bone reconstructive surgery as effective load-bearing grafts thanks to their ease of tailoring, bioactive properties and high mechanical strength. (C) 2009 Elsevier B.V. All rights reserved.