Studies on the effect of particle size on some properties of dental stone

Most indirect dental restorations of gold or porcelain are constructed on stone working models or dies. If these models or dies are damaged during the construction of these restorations in the laboratory, then the clinical success of the restoration will be jeopardized. This study is related to particle size, surface area, hardness and scratch resistance of twelve gypsum model or die materials. No correlation was found between particle size and hardness or scratch resistance. There was very little difference in hardness and scratch resistance between most of the materials tested.