Gingival retraction refers to the displacement of the free gingivae.
For crowns with margins which are supragingival, there is no need for gingival retraction, provided there is good moisture control.

For crown preparations which have subgingival margins, tissue control is necessary at the preparation stage and impression stage to ensure visibility, good moisture control and ensure enough bulk of impression material can be placed to accurately record the marginal areas.

Options available are gingival retraction cord, Magic Foam cord, and ExpaSyl.

Another method to expose the margins of a subgingival preparation is to use electrosurgery or crown lengthening surgery.
Gingival retraction refers to the displacement of the free gingivae. For crowns with margins which are supragingival, there is no need for gingival retraction, provided there is good moisture control.
For crown preparations which have subgingival margins, tissue control is necessary at the preparation stage and impression stage to ensure visibility, good moisture control and ensure enough bulk of impression material can be placed to accurately record the marginal areas.
Options available are gingival retraction cord, Magic Foam cord, and ExpaSyl.
Another method to expose the margins of a subgingival preparation is to use electrosurgery or crown lengthening surgery.
Crown (dentistry)