The American Dental Hygienists Association was formed in 1923 to develop communication and mutual cooperation among dental hygienists. ADHA is a national organization representing the professional interests of more than 120,000 registeered dental hygienists and over 10,000 dental hygiene students in more than 260 accredited dental hygiene programs throughout the United States. ADHA's foundation awards dental hygiene scholarships, research grants, fellowships and community service grants. ADHA is headquartered in Chicago.