Two different bioactive glasses and one glass-ceramic were implanted as granules for 2 months in rabbit muscle and for 5 months in sheep jaw in order to study the influence of the biological surroundings on the reactions of the materials.
Scanning electron microscope and energy dispersive X-ray microanalysis showed that a calcium and phosphorous-rich (CaP) surface layer (adjacent to a silicon rich-layer) forms on both glasses in both implantation sites. The glass-ceramic developed only a CaP layer. A chemical process of degradation was more evident in muscle, even though the implantation time was shorter than that in bone. For all materials, a chemical bond with bone occurs. The amount of new formed bone was different for the three materials.
Aging of the most reactive glass is hypothesized to explain a rapid loss of silicon by diffusion, as indicated by infrared spectroscopy.
Gatti, A. M.; Yamamuro, T.; Hench, L. L.; and Andersson, O. H.
"In-Vivo Reactions in Some Bioactive Glasses and Glass-Ceramics Granules,"
Cells and Materials: Vol. 3
, Article 5.
Available at: http://digitalcommons.usu.edu/cellsandmaterials/vol3/iss3/5