MODELWORK

Soft tissue material

Once the impression coping and analog assembly are properly repositioned in the impression, a soft tissue model needs to be created before pouring stone in to the impression. The soft tissue material can either be a rigid (Zhermack®, gingifast rigid) trimable type or a elastic (Zhermack®, gingifast elastic) non trimable type, depending on preference.

Separator

After applying a separator (Coltène®, GI-MASK™), extrude the material through a self mixing tip with a impression gun. Extend the material 2mm around the analog and 1mm above the mating surface of the impression coping and analog. Because the soft tissue material is quite runny, turn the impression up side down until the material has set.

Application

Subsequently pour the impression with stone as usual. Let the stone harden according to manufacturers specification. The mode of separating depends on the type of impression (direct, indirect or abutment level). For a direct impression the fixation screw that extends through the tray and connects the impression coping with the analog needs to be unscrewed and removed completely from the impression before separating the stone model from the impression. A abutment level and a indirect impression can be separated as is.

Finished soft tissue

Trim the resulting model rim in the usual fashion without exposing the analog with the model trimmer wheel. Base the rim and remove any indirect impression coping prior to mounting the model with the opposing model. Do not cut the analog section out as if it were a regular model for die trim.