Abstract : Biomaterials which me used in orthopaedic surgery, introduce the problem of their behaviour in body. When they me metallic it can happen a metal release. Ti6A14V titanium alloy is used for its good mechanical properties and its corrosion resistance. The use of coating makes it possible to improve its performance. I studied two glasses coatings referred BVA and BVH. The characterisation in vivo and in vitro was performed with several techniques of analysis: electronic microscopies and nuclear methods (PIXE, ...).
The BVA glass proved to be bioactive. It is transformed into a silicon gel with incorporation of proterns and trace elements (Zn and Sr), after 3 months of implantation. This gel disappears gradually and is replaced by neoformed bone. This bone is regarded as mature after me year of implantation; it ensures a better osseointegration of the implant. As far BVH glass, it is bioinert. Its composition is constant during time. However, the formation of an interface of 2 fan thickness, induced by the coating process, weakens the inter-granular connections. That results by the fragmentation of the coating and the migration of glass particles through the lacunar network of surrounding bone. Two glasses axe an effective barrier against the corrosion of alloy, as long as they remain in place.
I have proposed the bases of a new methodology of analysis : the combination of PIXE cartography and histopathology. The main interest is to correlate the possible tissue response to the presence of some atomic elements.
I have introduced for the fast time the percolation theory to model the resorption of porous biomaterials such as coral and hydroxyapatites. First simulations me very promising and me in good agreement with several experimental results observed.