Features of calcium phosphate plasma-sprayed coatings: an in vitro study.
Factors involved with the plasma-spray coating procedure, such as starting powder compound (fluorapatite, hydroxylapatite, magnesium-whitlockite, or tetra-calcium phosphate), powder particle distribution 1-45 or 1-125 microns), powder port gun (port 2 or 6), and post-heat treatment of 1 h at 600 degrees C, were examined for their effects on crystallinity and solubility/stability of the coating. From solubility tests, X-ray diffractometry, and scanning microscopy studies, the solubility and crystallinity were found to be dependent on Ca/P ratio, particle distribution, and post-heat treatment. The post-heat treatment influenced the degree of both crystallinity and solubility. The plasma-spray powder port factor for the hydroxylapatite coatings was not significant. Incubation in buffer of the coatings introduced precipitation at the surfaces of all non-heat-treated coatings except fluorapatite. No precipitation could be observed in any of the heat-treated coatings.
Klein
C P
CP
Department of Biomaterials, University of Leiden, The Netherlands.
Wolke
J G
JG
de Blieck-Hogervorst
J M
JM
de Groot
K
K
D002130:Calcium Phosphates / Q000737:chemistry; D003460:Crystallization; D006882:Hydroxyapatites; D008855:Microscopy, Electron, Scanning; D010316:Particle Size; D019736:Prostheses and Implants; D012995:Solubility; D013499:Surface Properties; D014961:X-Ray Diffraction
D002130:Calcium Phosphates; D006882:Hydroxyapatites