Expasyl, an alternative to retraction cord, is a viscous paste used for all procedures requiring surrounding structures retraction including: impressions, seating of provisional use, 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 professional use comfort. Expasyl is extruded directly into the sulcus where it holds its rigidity to create space between the tooth and the material, much like retraction cord. Bleeding and crevicular seepage are controlled through the presence of aluminum chloride, which also shrinks epithelial material – further expanding the sulcus.
