Epidemiologic observations of a dental condition common in certain areas and unknown in others led Dr. Frederick McKay to the recognition of an important factor in the development of the most ubiquitous of human ailments, dental caries. Over a period of 20 years, he studied the occurrence of mottled enamel, showed its relationship to some undetermined factor in the drinking water consumed during early childhood, and noted the frequent resistance of mottled teeth to decay. Following recognition of the role of fluorides in the development of this condition, Dr. H. Trendley Dean showed the relationship between the concentration of fluorides in water supplies and the development of mottled enamel and the prevalence of caries within a community.
These fundamental observations of Dr. McKay and Dr. Dean have opened a field of research to which many have subsequently contributed. Their studies have paved the way to the development of effective community-wide programs for the reduction of dental caries through the regulation of the fluoride content of public water supplies, a program of vital concern and great potential benefit to the health of mankind.