Fifty years of water fluoridation.

On January 25, 1945, the city of Grand Rapids, Michigan, began adding sodium fluoride to its drinking water. This action culminated a 14-year period of research which continues to have far-reaching effects on both public health and the practice of dentistry. The fact that the oral health of children and young adults today has never been higher is a direct consequence of this research. These events, and the group of rather extraordinary people who were the principal actors in them, are so important a part of dentistry's development that they are worth a brief retelling.