Osseous differentiation on freeze casted 10CeTZP-Al2O3 structures

Three-dimensional structures with directionally oriented pore networks were fabricated from a 10 mol% ceria-stabilized zirconia and alumina composite (10CeTZP-Al2O3) via freeze casting. Ceramic suspensions of different concentrations (30, 40 and 50 wt% solids) were frozen at various rates (2, 5 and 10 °C/min) to obtain lamellar structures with aligned tubular pores of different characteristics: porosity (75-84%), pore dimensions (small diameter of the elliptical pores: 10-23 μm; large diameter of the elliptical pores: ∼200 ± 70 μm), lamella thickness (2.7-4 μm) and compression strength (1-12 MPa). In vitro assays confirmed the non-cytotoxic nature of the samples. Furthermore, specific osseous differentiation genes were quantified after incubating osteoblasts on different cross sections of the samples during 7 days in supplemented culture medium; results demonstrated that the freeze casted structures induce up to nine times more osseous gene expression than tissue culture polystyrene (TCPS), an advanced surface used for optimized in vitro cell growth.