Shape memory alloy scaffolds for bone tissue engineering

Titanium alloy scaffolds for bone tissue engineering are receiving increasing attention because their porous structure and mechanical properties can be adjusted to match those of bone. In particular, there is an enormous potential to increase the life of such implant material if the porous structure can be imparted with shape memory properties. In the present study, TiNi scaffolds with a porous structure and high porosities up to 75% were fabricated by powder metallurgy. The porous structure was characterized by scanning electron microscope. The mechanical properties, the shape memory and superelastic effects were investigated by differential scanning calorimetry, nanoindentation and compressive tests. Results indicate that the porous TiNi scaffolds display an open-cell porous structure which provides new bone tissue ingrowth ability. The mechanical properties of the TiNi scaffolds can be tailored to match those of natural bone. Furthermore, the TiNi scaffolds show good shape memory and superelastic effects.