American Heart Association
The American Heart Association grew out of a set of smaller precursor groups. The primary precursor was the Association for the Prevention and Relief of Heart Disease, formed in New York City in 1915, to study whether patients with heart disease could safely return to work. Several similar organizations formed or evolved in Boston, Philadelphia, and Chicago in the 1920s. Recognizing the need for a national organization to share research and promote findings, the American Heart Association was formed in 1924 by six cardiologists representing several of these precursor groups.
American Dental Association
The American Dental Association was founded August 3, 1859, at Niagara Falls, New York, by twenty-six dentists who represented various dental societies in the United States. Today, the ADA has more than 152,000 members, 55 constituent (state-territorial) and 545 component (local) dental societies. It is the largest and oldest national dental association in the world and is committed to both the public and the dental profession.