Calcium sulfate bone scaffolds with controllable porous structure by selective laser sintering

The calcium sulfate (CaSO4) bone scaffolds with high porosity and interconnectivity and controllable pore size were prepared by using selective laser sintering. The phase composition, micro morphology and biocompatibility were investigated by using X-ray diffraction, scanning electron microscopy and microculture tetrazolium test. The results showed that the CaSO4 powders fused better and a more compact structure was built due to the decrease of holes in the scaffold at laser power of 7 W compared with 6 W or lower. At this time, both compressive strength and fracture toughness were optimal. While CaSO4 decomposed and resulted in the mechanical properties decreasing when laser power further increased. Consequently, the mechanical properties of the scaffolds decreased. Moreover, the osteoblast-like cells attached on the scaffolds were obtained by cell culture in vitro. The results revealed that the cells could adhere and grow well on the scaffolds.