New Technique Tries to Make the Fluoride Stick

A new way of applying fluoride to teeth could reverse small cavities, the American Dental Assn. says.

The new technique, being readied for tests on humans, makes the tooth enamel better able to react with and absorb fluoride, which prevents cavities. It could be applied the same way fluoride is applied today--in toothpaste, mouth rinses and gels, according to research chemist Laurence C. Chow of the dental association.

The new process uses calcium phosphate, which reacts with tooth enamel to form a natural mineral called dicalcium phosphate dihydrate. This in turn reacts with the fluoride, which bonds to the teeth in a form resistant to saliva. When small cavities have begun to form, it can halt and reverse the process, Chow said, who is awaiting federal approval for a three-year study on humans.