In vivo dissolution behavior of various RF magnetron sputtered Ca-P coatings

✍ Scribed by Wolke, J. G. C. ;de Groot, K. ;Jansen, J. A.

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 335 KB
• Volume: 39
• Category: Article
• ISSN: 0021-9304
• DOI: 10.1002/(sici)1097-4636(19980315)39:4<524::aid-jbm3>3.0.co;2-l

✦ Synopsis

Radiofrequency magnetron sputter deposition was used to deposit Ca-P sputter coatings on titanium discs, and these coatings were implanted subcutaneously into the backs of rabbits. Half of the as-sputtered coatings were subjected to additional heat treatment for 2 h at 500°C. X-ray diffraction (XRD) demonstrated that annealing at 500°C changed the amorphous sputtered coating into an amorphous-crystalline apatite structure. Scanning electron microscopic (SEM) examination of the sputtered coatings showed excellent coverage of the substrate surface. Annealing of the 4-m-thick coatings resulted in the appearence of small cracks. SEM demonstrated that until 4 weeks of implantation, all heat-treated coatings were present and all amorphous coatings were completely or mostly dissolved. Fourier transform infrared spectroscopy showed the formation of carbonate apatite (CO 3 -AP) on these specimens. Furthermore, XRD analysis showed that these CO 3 -AP precipitated coatings disappeared after 8 weeks of implantation. On the other hand, SEM inspection of these specimens revealed that the 4-m heat-treated coating was still partially maintained and that small Ca-P crystals were present on the titanium substrate. On the basis of these results, we conclude that apparently 0.1 m heat-treated Ca-P sputter coating is of sufficient thicknesses to stimulate carbonate apatite deposition under in vivo conditions.