Mladen Franz

The fatigue strength of the interface between Ag-Pd alloy and hydrothermal ceramic.

OBJECTIVE The purpose of this paper was to investigate the fatigue strength of a hydrothermal ceramic fused to Ag-Pd alloy. This study compared the values with those of other metal-ceramic systems previously reported by other authors. METHODS This investigation was performed on 48 specimens made of Ag-Pd alloy frames (45 x 12 x 4 mm) on which the hydrothermal ceramic was fused (25 x 12 x 2 gmm). The specimens were divided into two groups. The first group of specimens was dynamically loaded immediately after casting and fusing, while the other group of specimens was thermocycled (1000 times at 0 degree C and 55 degrees C) before dynamic loading. The dynamic loading tests were carried out by using a modified three-point load method in a universal testing machine. RESULTS The determined dynamic loading limit was up to 550 N for thermocycled, and up to 850 N for non-thermocycled specimens. These results are very respectable in comparison with other metal-ceramics. A statistically significant difference between maximal dynamic forces and number of loading cycles for thermocycled and non-thermocycled samples was determined. SIGNIFICANCE From the data obtained in this study and current literature profiles, it is concluded that the tested metal-ceramic system is more durable than other metal-ceramic systems.