Effect of porosity on the mechanical properties of bioactive foam scaffolds

Resorbable 3D macroporous bioactive scaffolds have been produced for tissue engineering applications by foaming sol-gel-derived bioactive glasses. The foams exhibit a hierarchical structure with interconnected macropores (10-500mum), which provide the potential for tissue ingrowth, and mesopores (2-50nm) that enhance bioactivity and resorbability. The compressive strength of the scaffolds was measured for different bulk densities (rho(b)) and porosities of the foams. Compressive strength generally increased as bulk density increased due to greater thickness of the pore walls, until a maximum of 1.36 MPa at rho(b) = 0.35, after which the foams became unstable due to cracks formed during the processing.