Date of Award
Spring 1996
Document Type
Thesis - Restricted
Degree Name
Master of Science (MS)
Department
Dentistry
First Advisor
Dhuru, Virendra B.
Second Advisor
Ziebert, Gerald J.
Third Advisor
Nagy, William W.
Abstract
This study was designed to evaluate the effect of the Deck-Gold coating agent on the metal-ceramic bond strength of porcelain fired on high-noble gold-palladium ceramic alloys by means of a three-point bend test. Four alloys were selected: Olympia, Collegiate. Deva-4, and Orion. Twenty rectangular metal strips from each alloy were cast. From these, ten were coated with DeckGold and the other ten were left uncoated. A standardized layer of VITA-Omega porcelain was fired on the metal strip in order to produce the final specimen. All specimens were tested on the three-point loading cell of an Instron Testing Machine. The failure load value of each specimen was recorded and converted to a bond strength ratio (BSR) value. The mean BSR values of the specimen groups were calculated and statistically analyzed. ANOVA, and Tukey tests identified and located differences among the uncoated specimens of all alloys as well as the coated ones. Paired comparisons with t-tests were used in order to detect difference between the coated and uncoated specimens of each alloy. After testing, all specimens were observed under an optical microscope and their failure mode was determined. Representative SEM photographs were taken. Among the four uncoated alloys, Collegiate had a significantly greater mean BSR value. The other three uncoated alloys were not statistically different. Among the four coated alloys, Orion exhibited a significantly lower mean BSR value, with the other three being not statistically different. Comparisons between the coated and uncoated specimens of each alloy showed that the mean BSR values of the coated Deva-4, Olympia, and Collegiate specimens were significantly greater than those of the uncoated ones. As for the coated Orion specimens, their mean BSR was slightly less but not statistically different from that of the uncoated ones. During testing, all coated specimens fractured with a crack perpendicular to the metal-ceramic bond area within the porcelain mass. The uncoated specimens fractured either with the above failure mode or with separation at one edge of the porcelain layer.
Recommended Citation
Kanellopoulos, Kanellos K., "The Effect of a Gold Coating Agent on the Porcelain to Metal Bond of Four High-Noble Metal Containing Casting Alloys" (1996). Master's Theses (1922-2009) Access restricted to Marquette Campus. 5230.
https://epublications.marquette.edu/theses/5230