SEM study of surface alterations of bioactive glasses and glass--ceramics in a bony implantation bed.

Back scattered electron (BSE) images of glasses and glass-ceramics with different degrees of bone-bonding behaviour have been investigated. After the implantation of probes in the femur of rats changes of the surface material, induced by leaching and corrosion (material response) and of the tissue in the drill hole (host response), were studied. The results demonstrate advantages of using BSE images and give further information for understanding the sequential changes in the implant material which occur mainly in bone-bonding materials. The density of the leached zone was not homogeneous and it therefore might be possible that preferential leaching of the glass matrix contributes to the mineralization of extracellular matrix. These findings could be of use for further development of surface reactive materials.