Dental Materials: Test 2 Flashcards
Classification for Impression Materials
Elastic: pick-up undercuts
Ridge: will not pick-up undercuts
Classification for elastic impression
Irreversible: will not return to original state (powder/liquid)
Reversible: will return to original state. ( only one impression is reversible)
Types of impression trays
Metal Perforated, Rim, Disposable plastic perforated trays, bite registration, triple trays, custom trays
Postitive impression
Poured impression in the stone known as diagnostic cast
die
replica of prepared tooth from working cast
Alginate composition
Agar (seaweed)
Polyvinyl composition?
Polyvinyl siloxane- ex. calking around a window
Polyvinyl armamentarium?
cartridges with mixing tip and mixing gun
polyvinyl tray?
disposable or quadrant
Alginate trays?
Max. 1-6 (1: smallest)
Mand. 20-26 ( 20-26) *20-24 most commonly used
Polysulfid Composition
Sulfide *oldest on market
Polysulfid Armamentarium
Catalyst and base, diamond head spatula, used in dentures
Polysulfid tray
Custom
Synersis
loss of water in an impression (alginate)
inhibition
uptake of water in an impression (alginate)
humidore
vessel used to store an impression (alginate) ex. tupperware container
Uses of dental waxes
lab work, cast, to hold things together, boxing, patterns
Composition of waxes
Mix of synthetic (fats, oils, resins, gums) and natural (minerals, beeswax, keratin,reason) waxes
Melting range of waxes
Range of temps that cause each component of the wax to go thru sulfide state
flow of waxes
Flows over what it needs to once in softened state
excess residue of waxes
remains after wax is removed
Classifications of waxes
Pattern, Inlay, Casting, Baseplate
Processing waxes
boxing, utility, sticky
Cons of Impression waxes
not accurate bite registration, almost obsolete, they distort
