Tray Material

Once the material is mixed, it is allowed it to cure until a dough-like consistency is reached. It can then be rolled out with the tray former to a uniform 2 mm thickness. A full sheet of the material is centered over each preliminary cast and gently adapted with the edge of a tongue blade. Material that extends beyond the edge of the preliminary cast is removed with a sharp scalpel and the material re-adapted to the preliminary cast. Care is taken to avoid trimming short of the tray borders that have been marked.

Forming the Tray Handle

To aid in the placement, positioning, and removal of the impression tray, a handle is fabricated from the same material as the impression tray.

Once the body of the tray has been formed but before the acrylic is set, the anterior central ridge crest area of the tray is lightly moistened with monomer. A handle formed from some of the trimmed-away excess is adapted and attached to the moistened area. The handle is angled perpendicular to the occlusal plane, so that it does not interfere with lip or tongue movements or position. Remove any excess material with a scalpel.

Trimming the Custom Tray

Trimming the fully set and cooled border of the impression tray can be accomplished with a carbide acrylic trimming bur. The tray should be trimmed so the border lines marked on the preliminary cast are just visible.

A properly made custom tray will be:

• Easily inserted and removed
• Stable
• Free of sharp edges
• Easily grasped by the handle