A dental mold is formed using, as a material, a mold material that formed
a first mold having a first mold surface, and has a second mold surface
different from the first mold surface. Alternatively, the material of the
mold material contains powder after use obtained by grinding the first
mold, and new powder added to the powder after use. The mold material is
a quick heating type gypsum bonded mold material, and contains 1% of at
least .alpha. gypsum. Alternatively, the mold material uses .alpha.
gypsum at 25 to 45% and at least one of quartz and cristobalite at 55 to
75%. Further, the mold material contains one of chloride and alum as an
additive.