Poor Bond Between Tray and Wash Material

Working time exceeded. +

Select material with sufficient working time and pay attention to storage temperature. Working times are reduced due to higher temperatures of the product, while intra-oral setting times might be longer if the temperature of the product is lower.

Initial impression not completely cleaned and dried (2-step technique). +

Clean the initial impression with plenty of water (or alcohol) and air. During this procedure, saliva has to be removed completely from the impression.Dry thoroughly before taking the second impression. Do not forget to clean and dry after try-in of first impression.

Sulfur or acrylic contamination of set initial impression (2-step technique). +

Use gloves which do not contain traces of sulfur, e.g. nitrile gloves. Do not use impressions already used to fabricate the provisional restoration for subsequent precision impression taking.

Relining of impression to correct defect in the impression. +

Do not try to reline impressions. This can lead to distortions and poor bond between new wash material and set material. Repeat the impression instead.