The major ingredient in Crest
was discovered by accident when a student left a sample in the
furnace too long and when discovered, found that it made it possible
to mix the ingredient with fluoride. At first it used stannous
fluoride, marketed as "Fluoristan" (this was also the original brand
name it was sold as. Later it changed from "Fluoristan" to "Crest
with Fluoristan"). The composition of the toothpaste had been
developed by Drs. Muhler, Harry Day, and William H. Nebergall at
Indiana University, and was patented by Nebergall.
Procter & Gamble paid royalties from use of the patent and thus
financed a new dental research institute at the university. The
active ingredient of Crest was changed in 1981 to sodium
monofluorophosphate, or "Fluoristat". Today Crest toothpastes use
sodium fluoride, or "Dentifrice with Fluoristat". Recently
introduced Crest Pro-Health, uses stannous fluoride again and an
abrasive whitener together called "Polyfluorite".