Compositions for reducing elution of therapeutic agents from teeth

Claim 1

A dentifrice composition for substantially effectively coating previously fluoride-treated teeth and thereby reducing elution of said fluoride from said teeth, said composition comprising a fluoride-containing caries prophylactic agent provided that said agent is substantially free from polyvalent metal atoms; and at least about 0.05% by weight of an anionic water-dispersible membrane-forming material which, when applied to the surface of said previously fluoride-treated teeth in an oral environment, complexes with the calcium of said teeth and forms a substantially continuous hydrophobic barrier thereon which substantially reduces the elution of said previously applied fluoride from said teeth and which, when at equilibrium with the complex, has a formation constant in the range of about 0.5 to 8, said anionic membrane-forming material being a non-polymeric fluorinated material selected from the group (R.sub.f SO.sub.2 N(R.sup.2)R.sup.3 O).sub.m PX(XB).sub.3-m (C.sub.g F.sub.2g+1 CH.sub.2 O).sub.k PO(OM).sub.q R.sub.f COOM R.sub.f R.sup.3 COOM R.sub.f SO.sub.2 OM .Iadd.R.sub.f SO.sub.2 OY .Iaddend. wherein R f is a monovalent, stable, inert, fluorinated, saturated aliphatic non-polar radical containing from about 4 to 16 carbon atoms; R 2 is selected from hydrogen and alkyl groups containing from about 2 to 3 carbon atoms; R 3 is selected from alkylene, chloro- substituted alkylene and alkarylene groups that contain from about 1 to 10 carbon atoms; X is selected from oxygen and sulfur; B is selected from hydrogen, alkali metal, ammonium and amine groups, and alkyl, aryl, cycloalkyl, alkaryl, and aralkyl groups each containing up to 20 carbon atoms; M is selected from hydrogen, alkali metal, ammonium and amine groups; .Iadd.Y is an aryl group; .Iaddend.m is 1 or 2; g is an integer of from 1 to 10; k is 1 or 2; and q is 3-k.