2TheApex: It’s PermaFlo Purple, a colored flowable composite.
Coronal seal has been shown to be critical in the long-term success of endodontic treatment. (click on “Coronal Seal” for flagship research on this subject) PermaFlo Purple is a flowable composite that will provide an excellent seal and is easily identifiable for when the Cavit is removed after treatment for the final restoration or if retreatment should needed in the future. It is useful in teeth that have deep caries or small crack making a coronal seal with Cavit questionable, or in patients that may have difficulty returning for a final restoration within the 30 days recommended following root canal treatment. It is bonded and placed as a thin layer, so does not need to be removed and can be bonded to just like any other composite restoration.