Importance of the physical parameters in the bone stimulation induced by active- surface glasses.

The present work analyses the in vivo behaviour of a bioactive glass that can be used for osteostimulation in bone defects. the glass called S53P4 was implanted as granules of 3 different sizes in pokets created in rabbit's dorsal muscles to investigate the reactions in the biological fluids. Before the implantation the granules were coated on one side with a layer of gold in order to obtain two sides with different permeability in the same granule and thus two differen velocities of diffusion. After 2 months granules were explanted and processed for observation under Scanning Electron Microscope with an X-ray microprobe in order to study the changed morphology of the granules and the distribution of the elements. The granules were partly leached but there were no signs of total glass breackdown and resorption.