What characteristic of retraction cord aids in its function?

Retraction cord is an important tool used in dentistry, particularly when preparing for procedures that require access to the gingival margin, such as impressions or crown placements. The characteristics of retraction cord can significantly influence its function.

The presence of impregnated substances is critical because these agents, which can include hemostatic or tissue-influencing substances, enhance the cord's ability to effectively manage bleeding and keep the operating field clean. For instance, cords may be impregnated with epinephrine or aluminum chloride, which constrict blood vessels and help control hemorrhage in the gingival area. This allows for better visibility and access during procedures, ensuring that dental professionals can work more effectively and safely.

While the size and elasticity of the cord play a role in how it engages with the gingival tissue, and color may aid in differentiating types of cords, the impregnated substances are what primarily provide the functional benefits necessary for retraction during dental procedures.