In vitro cytocompatibility, ageing and wear behavior of ceria stabilized zirconia bioceramic

Nano sized ceria stabilized zirconia (CSZ) powders were synthesized by co-precipitation method and then sintered conventionally to near full density. Ageing stability of developed materials was predicted through in vitro hydrothermal treatment in the presence of simulated body fluid (SBF). Fretting wear test at different loads was carried out using balls on flat geometry at different intervals of hydrothermal treatment to observe the effects of surface ageing on wear properties. Wear volume, specific wear rate and wear depth were estimated through 3D profile scan of the worn out surface by a surface profiler and it was found that the developed material became more wear resistant with the increase in hydrothermal treatment duration. XRD analysis and hardness study suggest that formation of orthorhombic zirconia during hydrothermal treatment improves the surface hardness (from 946±86 HV20 to 964±39 HV20 after 100 h of hydrothermal treatment) which in turn enhances wear resistance. In vitro cytocompatibility of the developed materials was inferred through the formation of hydroxyapatite-like layer on the surface of the material when soaked in SBF at 37.5 °C. Cytocompatibility was further ensured by studding attachment of multilayered human osteoblast cells (MG63) on the surface during cell culture.