For the two types of surfaces, GEE models demonstrated that unerupted surfaces were less likely to progress than sound surfaces.

No associations were found between reversals and independent variables.

The disclosure concerns an oral hygiene product which provides in the mouth a reservoir for the slow release of a therapeutic agent, such as fluoride ions.

It is well known to include water-soluble fluorine-containing salts, for example sodium fluoride or sodium monofluorophosphate, in oral products, especially mouthwashes and toothpastes, and that by regular use of such products the incidence of dental caries can be reduced.

The product comprises two compositions which are mixed in the mouth or before introduction into the mouth.

One composition comprises an aqueous suspension of particles which slowly release the therapeutic agent in salvia.

Fluoride is one of the most plentiful elements on Earth, and occurs naturally in both ground water and surface waters in Michigan.

When fluoride is present in drinking water at optimal levels, it has been shown to promote oral health by preventing tooth decay.