Cell Proliferation-Differentiation Behavior and Mechanical Properties of Alumina-Toughened Zirconia Composites with Controlled Surface Properties

Alumina-toughened zirconia (ATZ) composites are currently used as biomaterials in artificial hip joints. ATZ exhibits excellent mechanical properties and is resistant to degradation at low temperatures. However, it does not bond to biological bone after implantation because of its low bioactivity. In this study, the surface topology of ATZ was controlled to promote cell adhesion and proliferation, and the effect of the surface morphology on the mechanical properties was investigated. Micropatterning accelerated the progress of bone formation but reduced the strength to less than half the original strength. Specimens with a groove width of 0.1 mm, which is close to the cellular scale, showed the highest rate of bone formation under the employed conditions.