Kerr Dental Brand Dental Items Supplies, Recorder Code 261040 Expa-syl is a paste for gingival retraction that opens the sulcus and leaves the field dry. It is Safe and Painless Alternative to Packing Retraction Cord. It's injected directly into the sulcus, left for one to two minutes, then rinsed, physically displacing the tissue. Expa-syl holds its rigidity while in the sulcus to create space between the tooth and the tissue, much like retraction cord does. • Refill Package includes 40 Tips • Applicator tip may be bent