Microencapsulation and Release Profiles of Silver Diammine Fluoride Solutions

Objectives: The objective of this study was to synthesize novel fillers for dental materials containing aqueous solutions of silver diammine fluoride.
Methods: A heterogeneous polymerization technique was utilized to prepare microcapsules containing 50 w/w% silver diammine fluoride in water. The microcapsule particle size and particle size distribution were measured by scanning electron microscopy. Ion release profiles were obtained for silver diammine cations and fluoride anions from the microcapsules. Dialysis tubing was filled with microencapsules that contained silver diammine fluoride solutions. The dialysis tubing was submerged in nanopure water. The ion release was measured as a function of time. A method was developed to determine fluoride ion concentration by ion specific electrodes in the presence of silver ions. Atomic absorption was used to determine the silver ion release profile.
Results: Scanning electron microscopy provided support for the successful synthesis of microcapsules containing aqueous solutions of silver diammine fluoride. The particle size and particle size distribution was determined as a function of reaction synthesis conditions. Silver diammine cation and fluoride ion release was demonstrated from the microcapsule as a function of time.
Conclusions: Recently, the use of silver diammine fluoride for the treatment of caries has been reported. The current treatment option using silver diammine fluoride involves the direct application of the aqueous solution to the tooth. Microencapsulation of silver diammine fluoride can potentially allow for longer term therapeutic treatment by controlling the rate of release of the silver diammine cations and fluoride anions from a wide range of dental materials.