The effect of abrasive blasting on the strength of a joint between dental porcelain and metal base.

This paper presents the effect of selected parameters of abrasive blasting on the strength of a joint between dental porcelain and metal base. Experiments were conducted for different grain sizes of abrasive material and different blasting angles, with a constant blasting pressure. InLine dental porcelain was fused on samples of cobalt-chromium alloy following abrasive blasting; they were subsequently subjected to shearing forces on a testing machine. The fractures were observed under an electron scanning microscope in order to determine the character and course of fracturing. Strength tests showed that the grain size of abrasive material was a parameter with the greatest effect on the strength. The best effects were achieved for samples subjected to abrasive blasting with material with grain size of 110 μm. No statistically significant differences were found for the strength of samples worked at different angles. The results of the fractographic examinations have shown that in all the samples, fracturing occurred mainly along the porcelain-metal boundary, with few cases of fracturing through porcelain.