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Alginate impression setup

Also called: study model impressions, prelim impressions

Setup for quick impressions of both arches for study models or appliances.

Alginate impressions copy the teeth for study models, mouth guards and other appliances. Try in trays first, mix powder into room-temperature water, load the tray, seat it, wait for it to set, then remove it with one quick snap. Rinse, disinfect and pour or bag it promptly. Every office's tray list is a little different; this is a common example. Follow your office's tray card.

How to spot it

  1. Upper and lower stock trays, a flexible bowl, wide spatula and alginate measures.

On the tray, in order

  1. 1. Upper and lower stock trays (tried in for size)
  2. 2. Alginate powder and scoop, water measure
  3. 3. Flexible rubber bowl and alginate spatula
  4. 4. Wax or utility wax for tray edges (if used)
  5. 5. Saliva ejector, gauze, air-water syringe tip
  6. 6. Bite registration material (if needed)
  7. 7. Disinfectant spray and a labeled bag

Safety and care

  1. Seat the patient upright with the head tilted slightly forward and have them breathe through the nose to limit gagging.
  2. Disinfect impressions before they leave the operatory.

Related

Sources: British Orthodontic Society. The Taking of Alginate Dental Impressions (nurse training handout), CDC. Guidelines for Infection Control in Dental Health-Care Settings, 2003. MMWR 2003;52(RR-17), Colgate. Getting a dental impression: how to cope with your gag reflex