Definitive Casts and Dies Flashcards
A replica of the tooth surfaces, residual ridge areas, and/or other parts of the dental arch and/or facial structures used to fabricate a dental restoration or prosthesis:
Definitive (master or working) cast
Definitive cast =
master or working cast
The positive reproduction of the form of a prepared tooth in any suitable substance:
die
A metal pin used in some stone casts to remove die sections and replace them accurately in the original position
die pin
In a die, the unprepared tooth structure apical to the finish line should be easily visible at:
0.5-1.0mm
Advantages of gypsum products:
- compatible with all impression materials
- ability to reproduce fine detail and sharp margins
- dimensional accuracy and stability
- easy to use
What is the disadvantage of gypsum products?
Susceptibility to abrasion
ADA Type I & II Gypsum productions
Impression plaster/ model and mounting plaster
(PLASTER)
ADA Type III Gypsum products:
Dental stone
(general purpose cast)
ADA Type IV Gypsum products:
High strength/Lowest expansion
(Die stone)
ADA Type V Gypsum products:
High strength/ High expansion
(Die stone)
What are the advantages of auto mixing a gypsum product?
- homogenous
- more strength
- intended expansion
What is directly proportional to the water powder ratio of gypsum products?
setting times and manipulation
Regarding the water to powder ratio of gypsum productions:
Describe the directly proportional relationship with increased water:
Increased water = increased setting time; increased fluidity
What is indirectly proportional to the water powder ratio of gypsum products?
compression strength and setting expansion