BIOACTIVE GLASS-CERAMIC FILMS BY PULSED-LASER DEPOSITION

The pulsed laser deposition (PLD) method is used to ablate glass-ceramic targets and to produce thin films on biocompatible substrates (titanium alloys and polytetrafluoroethylene). The measured etching rates of about 0.1 mu g/pulse have been induced by a pulsed excimer laser (308 nm wavelength) in the ''Calcigraft'' bioactive glass ceramics. Using a laser pulse frequency of 20 Hz, the deposition rate on a titanium substrate, in vacuum conditions and at room temperature, is of the order of 1 mu m/min. Deposited films have been characterized in stoichiometry, thickness, morphology and substrate adhesion by RBS, PIXE and SEM analysis. Films can be employed to cover medical devices, such as dental roots and middle ear prostheses, to improve their osteointegration with the biological tissues.