CO₂ laser irradiation of a magnesia partially stabilized zirconia (MgO-PSZ) bioceramic and the subsequent improvements in human osteoblast cell adhesion

Osteoblast cells were used in an in vitro test to examine changes in cell adhesion on a magnesia partially stabilised zirconia (MgO-PSZ) bioceramic after CO₂ laser treatment. The surface roughness, microstructure, crystal size and surface energy of untreated and CO₂ laser treated samples were fully characterized. After 24 h cell incubation, no cells were observed on the untreated MgO-PSZ, whereas cells were seen to have attached onto the CO ₂ laser treated MgO-PSZ and exhibited spreading and good attachment. Moreover, the cell coverage density implied an increase in cell proliferation with increasing CO₂ laser power density. Enhancement of the surface energy of the MgO-PSZ, especially its polar component, caused by the CO ₂ laser treatment was found to play a significant role in the initial cell attachment process, thereby leading to enhanced cell growth. Also, the change in topography induced by the CO₂ laser treatment was identified as one of the factors influencing the osteoblast cell response.