The effect of addition of calcium hypochlorite disinfectant on some physical and mechanical properties of dental stone


Background: The potentially damaging effects of the immersion technique, the difficulty in covering the entiresurface of the cast with the spray disinfecting solution, and the inability to assume that every impression presented tothe laboratory has been disinfected has led to the need for incorporating a disinfectant directly into the calciumsulfate hemihydrate. This study was designed to evaluate the effect of the addition of Calcium Hypochoritedisinfectant on some physical and mechanical properties of the dental stone.Materials and methods: Calcium Hypochlorite disinfectant in aqueous solution in different concentrations 0.5, 1.0, 1.5and 2.0% was added to type III dental stone. Setting time, setting expansion, reproduction of details, compatibilitywith impression materials and consistency are physical properties which were evaluated. The compressive strengthand surface hardness as mechanical properties were also determined.Results: The results of this study showed that the addition of 1 % of calcium hypochlorite improved some of thephysical and mechanical properties of dental stone (Setting Expansion, Compressive Strength and Surface Hardness)while its adversely affected the other properties (Setting Time)Conclusions: The 1 % of calcium hypochlorite disinfectant solution could be used to disinfect dental cast with theleast effect when compared with the other concentrations of calcium hypochlorite