The influence of different fluoride compounds and treatment conditions on dental enamel: a descriptive in vitro study of the CaF(2) precipitation and microstructure.

Electron and atomic force microscopy techniques have been applied to characterize both the in vitro deposition intensity and the microstructure of the KOH-soluble fluoride precipitates on human dental enamel. The study was focused on the effects of amine fluoride, sodium fluoride and sodium monofluorophosphate having a fluoride concentration of 0.1% F in acidulated and aqueous solutions. Under certain conditions, fluoride globules were formed within an initiation time of less than 20 s. This result supports the potential significance of this process for the cariostatic action of fluorides during dentifrice use. The deposition intensity seems to be dependent on the availability of Ca and F ions on the dental surface. A nanocrystalline calcium fluoride-like microstructure was revealed, with an additional phosphorus and oxygen incorporation as a function of the treatment time.