Journal of Dental Research, Vol 66, 1717-1720, Copyright © 1987 by International & American Associations for Dental Research Online Journals
Experimental observation of silver and gold penetration into dental ceramic by means of a radiotracer technique
F. Moya, J. Payan, J. Bernardini and E. G. Moya
Laboratoire de Metallurgie, Faculte des Sciences et Techniques de St. Jerome, AV. Escadrille Normandie Niemen, Marseille, France.
A radiotracer technique was used to study silver and gold diffusion into
dental porcelain under experimental conditions close to the real conditions
in prosthetic laboratories for porcelain bakes. It was clearly shown that
these non-oxidizable elements were able to diffuse into the ceramic as well
as oxidizable ones. The penetration depth varied widely according to the
element. The ratio DAg/DAu was about 10(3) around 850 degrees C. In
contrast to gold, the silver diffusion rate was high enough to allow
silver, from the metallic alloy, to be present at the external ceramic
surface after diffusion into the ceramic. Hence, the greening of dental
porcelains baked on silver-rich alloys could be explained mainly by a
solid-state diffusion mechanism.
