Dental materials
(gypsum) questions
and answers (verified
for accuracy)
Chemical formula for gypsum is... - answer CaSO4 2H2O
Gypsum is... - answer Calcium sulfate dihydrate
Weakest type of gypsum? What particles does it contain? - answer
Plaster. Irregular, spongy, and small.
Stronger type of gypsum? (Not strongest). What particles does it
contain? - answer Yellow stone (Class I). More regular, larger.
Strongest type of gypsum? What particles does it contain? - answer
Improved stone (Class II). Very uniform, high strength, very dense
During calcination, heat is added to remove water to make powder.
What is the chemical formula for the resulting powder and what is it
called? - answer CaSO4 1/2H2O. Calcium sulfate hemihydrate
When water is added to a hemihydrate what is produced? - answer
Dihydrate
, When strength isn't important what gypsum product is used? -
answer Plaster
Plaster is used for....? - answer Study casts and articulation
models.
Dental stone (Class I stone) is used for...? - answer Working models
High strength stone (Class II stone) is used for...? - answer Die
construction (one prepared tooth), and models for partial dentures.
What type of gypsum is used when strength is most important? -
answer Class II stone
When mixing plaster or stone ____ is placed in the bowl first and
then ____ is added. - answer Water. Hemihydrate (powder).
A ____ motion should be used. A ____ can be added to the mix to
eliminate bubbles. Bubbles will ____ the model. - answer Slow
stirring. Vacuum. Weaken
The formula for calcium sulfate hemihydrate is...? - answer CaSO4
1/2H2O
The setting action of stone and water results in the release of... -
answer Heat
The measure of speed with the mixture of hemihydrate and water
changes to the rigid solid is know as.... - answer Setting time
Plasters and stones have 2 sets. The first is the ____ set, and the
second is the ____ set. - answer Initial. Final.
(gypsum) questions
and answers (verified
for accuracy)
Chemical formula for gypsum is... - answer CaSO4 2H2O
Gypsum is... - answer Calcium sulfate dihydrate
Weakest type of gypsum? What particles does it contain? - answer
Plaster. Irregular, spongy, and small.
Stronger type of gypsum? (Not strongest). What particles does it
contain? - answer Yellow stone (Class I). More regular, larger.
Strongest type of gypsum? What particles does it contain? - answer
Improved stone (Class II). Very uniform, high strength, very dense
During calcination, heat is added to remove water to make powder.
What is the chemical formula for the resulting powder and what is it
called? - answer CaSO4 1/2H2O. Calcium sulfate hemihydrate
When water is added to a hemihydrate what is produced? - answer
Dihydrate
, When strength isn't important what gypsum product is used? -
answer Plaster
Plaster is used for....? - answer Study casts and articulation
models.
Dental stone (Class I stone) is used for...? - answer Working models
High strength stone (Class II stone) is used for...? - answer Die
construction (one prepared tooth), and models for partial dentures.
What type of gypsum is used when strength is most important? -
answer Class II stone
When mixing plaster or stone ____ is placed in the bowl first and
then ____ is added. - answer Water. Hemihydrate (powder).
A ____ motion should be used. A ____ can be added to the mix to
eliminate bubbles. Bubbles will ____ the model. - answer Slow
stirring. Vacuum. Weaken
The formula for calcium sulfate hemihydrate is...? - answer CaSO4
1/2H2O
The setting action of stone and water results in the release of... -
answer Heat
The measure of speed with the mixture of hemihydrate and water
changes to the rigid solid is know as.... - answer Setting time
Plasters and stones have 2 sets. The first is the ____ set, and the
second is the ____ set. - answer Initial. Final.
