Nice goal dance there. You spoke of sodium fluoride and are now pretending sodium fluosilicate is the same. In low concentrations, fluosilicate decomposes to the active which is, guess what, fluoride ion.
I never said they were the same, but sodium fluosilicates are what is used to fluoridate water and damage human health as well (http://www.ncbi.nlm.nih.gov/pubmed/17420053). Also, I may have been mistaken, sodium fluoride is added to toothpastes, mouthwash, and other products while sodium fluosilicates are used for tap water. Nonetheless... Calcium Fluoride does not break up into ions very well, so it does not dissolve very well. But at 1ppm most if not all of the dissolved Calcium Fluoride has split up into Calcium ions and Fluoride ions. Silicofluorides are much more soluble than Calcium Fluoride, and ionise in a 2-stage process. However they do not completely break down into Fluoride ions. This was shown by Crosby in 1969. The dissociation was between 87% and 95%. Crosby is constantly misquoted as proving the dissociation was 100%, which is incorrect. More importantly, all components remain available for chemical reaction, so whether the substance has fully ionised or not is in this respect irrelevant. Further, when silicofluorides are put in acidic conditions, such as stomach acid, they tend to return to the molecular form (the dissociation constant shifts). According to WHO (2006) 50% of fluoride in the stomach is absorbed as molecular hydrofluoric acid, the most corrosive acid known, and which can attack DNA (i.e. is mutagenic/carcinogenic).