Fluoride uptake and retention in vitro following topical fluoride applications.

Fluoride uptake and retention on maxillary and mandibular incisors were compared using a conventional APF gel, a thixotropic gel, and a new pluronic-based fluoride gel. Based on the results of in vivo acid-etch biopsies, significant fluoride uptake was obtained with each of the three agents. The highly viscous pluronic gel may provide an alternative to conventional topical fluoride gels for subjects--e.g., handicapped persons--with whom a tray system is not feasible.