Effect of loading weight on bond durability of composite-type resin cement under cyclic impact test (part 2). Loading with light weight of 100-120 g

The bond durability of composite-type resin cement was evaluated by means of cyclic impact tests using three different loads. In terms of experimental setup, a casting alloy, 12％Au-Pd-Ag, was used as the adherend and bonded to a cast block using a composite-type cement (Bistite II). A shear load ― using plungers of three different weights at 100, 110, and 120 g ― was dropped from a 3-mm height onto a small piece of the casting alloy until debonding. The cycle numbers that caused debonding were 1756±680 × 10 4 times for 100 g, 1403±515 × 10 4 times for 110 g, and 420±200 × 10 4 times for 120 g, respectively. Therefore, the group loaded with 120 g showed a significantly lower value as compared to the other two groups. On the fracture mode of the cement, it was a bulk fracture regardless of the loading weight employed in this study ― the same result obtained in a previous study where heavier weights were employed.