Impression Trays And Their Uses

Table of Contents

Impression trays are used in conjunction with various types of materials to take imprints of the patient’s dentition. The type of tray chosen depends on the type of impression needed and the procedure that is indicated.

USES AND FEATURES OF IMPRESSION TRAYS

Used to hold impression material
Can be perforated for better retention
Have a handle for better grasp during placement and removal
Dentate impression trays – for patients with teeth
Edentulous impression trays – for patients with no teeth

5 TYPES OF IMPRESSION TRAYS

Metal perforated type trays
Plastic-type/stock tray
The universal sectional impression tray
Custom tray/special tray
Triple tray.

Metal perforated type trays

Features

Autoclavable
Available in different sizes (denoted by numbers)
Not easily adapted
Available as solid metal trays

Plastic-type/stock tray

Features

Disposable, single-use
A tray adhesive may be used for added retention of impression material
Available in different sizes (denoted by colours)
Can be adapted using a heat source

The universal sectional impression tray

Used and features

The modified tray used to take an impression of a specific area of the mouth
Maybe perforated for retention
Fabricated from flexible metal – adaptable
Only suitable for dentate patients
Autoclavable

Custom tray/special tray

Features

Fabricated from a plaster model of the patient’s dentate or edentulous arches
Fabricated from an acrylic material
Disposable, single-use
Must be ‘painted’ with tray adhesive for retention of impression material

Triple tray

Uses and features

Used to take an impression of both arches simultaneously
Fabricated from a combination of plastic and flexible webbing material
Many different sizes available (anterior, posterior, quadrant)
Disposable, single-use
Must be painted with tray adhesive for retention of impression material

Impression Trays Set-up

Set-up for taking an impression. Set-up will vary depending on the type of impression being taken.

Desired impression material
Desired type of impression tray, tray adhesive and applicator brush
If required, mixing spatula, mixing bowl and water measure
Kidney dish – in case of a gag reflex when taking impressions.
Tissues and rinse cup for patients
Wax may be required if the tray needs to be extended
Laboratory prescription form and laboratory bag
Red ribbon wax.
Equipment/materials for disinfection of impression prior to sending to the laboratory