Thumb impression ||impression compound||Dr Raj Dentistry||

Описание: ‪@DrRajdentistry-k5v‬
thumb impression
impression compound

What is Impression Compound?
Impression compound is a thermoplastic (heat-softened) material used to make preliminary dental impressions, especially for edentulous (no-teeth) patients. It becomes soft when heated and hardens again when cooled.

Composition

Impression compound typically contains:
Resins (e.g., natural resins, shellac) – provide rigidity
Waxes (e.g., stearic acid) – help soften at lower temperatures
Fillers (e.g., talc) – give strength and body
Colorants – provide contrast

Types

Type I – Low fusing (Impression compound)
Softens at ~55–60°C
Used for making impressions

Type II – High fusing (Tray compound)
Softens at ~70–80°C
Used for making custom trays or border molding

Properties

Advantages

Reusable
Non-toxic, non-irritant
Good dimensional stability once cooled
Easy to handle for border molding

Limitations
Low accuracy compared to elastomers
Cannot record fine details
Distorts if removed from the mouth while still warm
Must be tempered carefully
Manipulation (How it’s used)
Soften the compound by heating it in a water bath (never flame directly).
Load it onto the impression tray.
Insert into the mouth and let it cool to become rigid.
Remove the impression once firm.
Chill under cold water to stabilize dimensions

Uses in Dentistry
Preliminary impressions for complete dentures
Border molding of custom trays
Recording impression for edentulous ridges
Making bite blocks
Extending tray flanges