PROBLEM TO BE SOLVED: To provide a dental gypsum-based implant material for dental press ceramic, dental press resin and high-melting-point metal casting, which solves the problem of deterioration of strength at high temperature.SOLUTION: A dental gypsum-based implant material has (a) powder material containing hemihydrate gypsum, and (b) liquid material containing colloidal silica aqueous solution. At least one of the (a) powder material containing hemihydrate gypsum, and (b) liquid material containing colloidal silica aqueous solution contains (c) magnesium sulfate.SELECTED DRAWING: NoneCOPYRIGHT: (C)2020,JPO&INPIT【課題】 高温での強度低下の問題点を解決した、歯科用プレスセラミックス、歯科用プレスレジン及び高融点金属鋳造用の歯科用石膏系埋没材を提供する。【解決手段】本発明の歯科用石膏系埋没材は、(a)半水石膏を含む粉材、及び、(b)コロイダルシリカ水溶液を含む液材を含み、(a)半水石膏を含む粉材及び(b)コロイダルシリカ水溶液を含む液材の少なくとも一方に、(c)硫酸マグネシウムを含むものである。【選択図】なし