Joseph C. Muhler presents toothpaste and toothbrushes to two of the 12,000 young volunteers who took part in tests of a stannous fluoride toothpaste. The Monroe County History Center opened a new exhibit May 21 highlighting Crest toothpaste, which Muhler and two other IU scientists formulated. IU Archives Buy Photos

Crest began selling a new type of toothpaste utilizing fluoride to prevent cavities in 1956, according to the history center’s exhibit.

IU historian and adjunct professor James Capshew said Joseph Muhler began to research fluoride as a dental student at IU-Purdue University Indianapolis in the 1940s. In 1951, Muhler began working on a new fluoride toothpaste alongside IU professors Harry Day and William Nebergall using funding from Procter and Gamble, the company that owns Crest, according to the history center’s exhibit.

The challenge was finding an element they could combine with fluoride and not lose the anti-cavity effects. Capshew said the scientists discovered fluoride and tin could be successfully mixed without degrading and began creating Crest prototypes.

Gianopoulos said the scientists had Bloomington children test the product. Children received free dental checkups during a time when many families could not financially prioritize dental health.

Half of the children received a placebo toothpaste, and the other half received a stannous fluoride toothpaste, Gianopoulos said. The scientists found in some groups children had nearly 50% fewer cavities after using Crest.

Gianopoulos said children from the trials and their families participated in commercials advertising Crest toothpaste.

Many current Bloomington residents reached out the history center to say they had participated in the trials, education manager Andrea Hastell said.

The exhibit will conclude Oct. 12.

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