How long will the retraction effect with ASTRINGEDENT/VISCOSTAT carry on after the cord is pulled out?
One of the primary effects of astringent displacement chemicals is their ability to affect the collagen memory of the gingival tissues. Ramadan published in the Egyptian Dental Journal that the astringent effect can provide retraction for up to 23 minutes in dogs. The critical issue here is the application time necessary for the chemical to produce this level of effect. ViscoStat requires only 1 to 3 minutes of application in a blood-free sulcus to provide adequate space for impression-making procedures. An evaluation of closure times has not been performed on ferric sulfate materials. Clinical experience has established that the 1 to 3 minute application time will provide several minutes of viable retraction for the majority of patients.
