Fluoride-releasing acrylics.

There are numerous examples in dentistry where demineralization, or even frank caries, develops near or in association with restorative or prosthetic materials. Leaking cavity margins and demineralization under bite splints are two examples. A slow-release source of fluoride could help to prevent these problems and provide added protection throughout the mouth. For this purpose a family of fluoride-releasing resins has been developed for use in various adhesive applications, and also for preparing temporary crowns and removable acrylic devices. These materials contain fluoride ions held to covalently bound positive charge sites within the polymer network. Release is by a diffusion/exchange mechanism in which anions from oral fluids diffuse to the charge sites and exchange with fluoride. Fluoride then diffuses to the surface and is released into solution. This method of release allows for the retention of adequate physical properties and is capable of a linear release rate for terms ranging from days to years.