| Abstract: | Metallic implants are widely used in orthopaedic surgery but metal release has been reported by several authors. High metallic ion concentration in surrounding tissues may play a major role in therapeutic failure. We have investigated in vivo and in vitro two biological glasses (BVA and BVH) used as coatings of metal implants. Physicochemical characterization was made by several complementary methods, particularly particle induced x‐ray emission (PIXE) and energy‐dispersive x‐ray spectroscopy (EDXS) associated with electronic microscopy. Analyses clearly show the differences of behaviour between both glasses. The BVA glass is bioactive, i.e. it develops a direct chemical bond between prosthesis and bone by the formation of a calcium phosphate layer at its surface. These structural and compositional modifications are caused by hydrolysis of the glass. After its dissolution BVA glass is replaced by bone, which ensures better integration of the implant in the bone site. The BVH glass is not bioactive and is used as a cement to isolate the metal implant from the biological environment, but the coating disaggregates with implantation time and glass grains migrate through the bony lacuna network. Copyright © 2003 John Wiley & Sons, Ltd. |
