Expasyl, an alternative to retraction cord, is a viscous paste used for all procedures requiring gingival retraction including: impressions, seating of restorations, fitting rubber dams, and restoring class II, III, and V cavities. Unlike cord, you need little or no pressure to apply Expasyl, which greatly minimizes the risk of rupturing the epithelial attachment and enhances patient comfort. Expasyl is extruded directly into the sulcus where it holds its rigidity to create space between the tooth and the tissue, much like retraction cord. Bleeding and crevicular seepage are controlled through the presence of aluminum chloride, which also shrinks epithelial tissue – further expanding the sulcus.
