Does fluoride found naturally in water work in a different way to fluoride added to water?
The calcium fluoride in naturally fluoridated water dissociates (splits up) to produce free fluoride ions. Hexafluorosilicic Acid which is used to fluoridate water artificially also splits up to form free fluoride ions. Although the compounds are very different they both split to form fluoride ions. As both waters contain free fluoride ions there is no difference between the actions of the naturally and artificially fluoridated water.