[Effect of the treatments preceding porcelain baking on the strength of the ceramic-metal bond].
The influence of various prefiring treatments of the metallic structure on the metal-ceramic bond strength has been shown for a gold-platinum ceramic alloys. Using analytical techniques with a high sensitivity, it has been possible to show that indium accumulates considerably on and below the metallic surface and that a subsequent sand blasting or acid pickling (hot diluted sulfuric acid) brings the indium level down to the initial value of the alloy. Changes in the resulting mean coefficient of thermal expansion have been computed and verified experimentally. They have then been correlated with the mechanical behavior of the tested metal-porcelain bonds. It has thus been shown that a preliminary oxidation in the air, followed by a hot acid pickling, is the best prefiring procedure. The superficial indium concentration is more homogeneous and closer to the initial content and the bond strength thus obtained is among the highest, with the lowest dispersion. This procedure enables to enhance the fiability on the porcelain-baked-to-metal technique and to increase the safety margin of the bond itself.
D003722:Dental Alloys / Q000032:analysis; D001840:Dental Bonding; D003776:Dental Porcelain / Q000032:analysis; D010084:Oxidation-Reduction; D013314:Stress, Mechanical; D013674:Technology, Dental
D003722:Dental Alloys; D003776:Dental Porcelain
Influence des traitements précédant la cuisson de la porcelaine sur la résitance de la liaison céramo-métallique.