Prosthodontics: Alginate Impressions
What is Alginate?
Impression materials are often classified according to their properties.
A poorly executed alginate impression
What type of impression material is alginate?
Why is the setting reaction of alginate irreversible ?
What is a colloid? And a hydrocolloid?
Alginate goes through two phases before setting:
-
SOL formation, which is the stage at which it should be inserted in the mouth when
it is sufficiently fluid to record detail. No gelation should occur at this stage. -
GEL formation is the stage at which fibrils are formed and alginate goes
through an irreversible setting process. It is after this stage that the tray should be removed.