Synthesis of functional gradient BCP/ZrO 2 bone substitutes using ZrO 2 and BCP nanopowders

Abstract

BCP/BCP–ZrO 2/ZrO 2 scaffold with a functionally gradient layered structure (FG BCP/ZrO 2) was fabricated by the polymeric sponge replica method and subsequent dipping process. To enhance the compressive strength and bioactive properties of monolithic ZrO 2 scaffold, ZrO 2 and BCP phases were selected as a main frame and surface layer, respectively. The formation of microcracks was significantly decreased by incorporating an intermediate layer consisting of BCP–ZrO 2 phase. The thicknesses of the monolithic ZrO 2, BCP–ZrO 2, and BCP layer were around 10–30 μm, 3–5 μm, and 2–3 μm, respectively. The FG BCP/ZrO 2 scaffold showed highly interconnected pores as well as good material properties, which were 68% porosity and 7.2 MPa of compressive strength. Average pore size of FG BCP/ZrO 2 scaffold was about 220 μm in diameter. From MTT assay and SEM observation of osteoblast-like MG-63 cells, FG BCP/ZrO 2 scaffold showed good cell viability and faster proliferation behavior.