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Related to dental plaster: dental stone
A powder, when mixed with water, that hardens to form a stonelike investment or model material. It is composed of a hemihydrate of gypsum (CaSO4·2H2O), which differs in compression strength and expansion coefficient according to how it is treated and rehydrated. There are four classes of dental plaster, with differing uses as materials for casts, impressions, or stone models, based on the differences of characteristics.
See also: plaster
den·tal plas·ter(dentăl plastĕr)
Beta form of calcium sulfate hemihydrate; a fibrous aggregate of fine crystals with capillary pores that are irregular in shape and porous in character; also referred to as plaster of Paris.