A custom impression tray made with the aid of an existing prosthesis: a clinical technique.

Prostheses for patients with intraoral defects usually have complex contours. The replacement of a successful prosthesis is more readily accomplished with the aid of a custom impression tray that reproduces the contours of the existing prosthesis. In the technique presented, an irreversible hydrocolloid impression is made of the intaglio surface of the prosthesis to be replaced. Autopolymerizing acrylic resin tray material is poured into the impression, creating a custom impression tray. This procedure can simplify the impression process and reduce the need for multistep impression techniques.