The dental profession has prime responsibility for the care of oral health problems in the U.S. Medicine has essentially relinquished responsibility for that part of the body. Dental public health primarily evolved from within the dental profession and it is unique in that a special area in public health was created to address the problems of a particular part of the body. Although one may not think of the major dental diseases--dental caries and periodontal disease--as particularly serious ones, the magnitude of the problem, as evidenced by the universality of the diseases and the extensive levels of untreated pathology, results in a public health problem of major proportions. The field has been expanding in scope and complexity with more emphasis being placed on the total dental care delivery system and its impact on oral health status. The concept of oral health has a very different meaning and value for people in different cultures and socio-economic classes. The prevalent philosophy in the U.S. places the prime responsibility for dental health on the individual.