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Stock impression trays

Also called: impression tray, stock tray, rim-lock tray, perforated tray

U-shaped trays that carry impression material over a whole arch.

Stock trays come in sizes for upper and lower arches. Upper trays have a palate section; lower trays have an open space for the tongue. Metal trays are reusable; plastic trays are often disposable. Perforations or rim-locks help the material stay in the tray.

How to spot it

  • Upper: covers the roof of the mouth. Lower: horseshoe shape open in the middle.
  • Holes (perforations) or a rolled edge (rim-lock).

What it is used for

  • Try in for size first: it should cover all teeth without pressing on tissue.
  • Alginate or other material is loaded and seated.

Safety and care

  • Semicritical item (it touches the inside of the mouth): clean it, package it and heat-sterilize it after every patient. (Reusable metal trays only; plastic trays are single-use.)
  • Rinse and disinfect impressions before sending them to the lab.

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)