Working time of dental amalgams

The purpose of the present work was to study the setting of amalgams made from several different commercial alloys by recording the rate of initial mercury consumption, and then to compare the findings with those from other methods of defining the early setting process. The results show that the rate of initial mercury consumption is well correlated with clinicians' classification of the rate of setting of amalgams, but not correlated with mechanical tests like early compressive strength and guillotine setting time used till now in estimating the working time of amalgams. Based on these findings an appropriate method of determining the mercury:alloy proportion and working time of dental amalgams is suggested.