Journal of Periodontology 75th anniversary. Special feature.
D049672:History, 19th Century; D049673:History, 20th Century; D006801:Humans; D010506:Periodicals as Topic / Q000266:history*; D010517:Periodontics / Q000266:history*; D012953:Societies, Dental / Q000266:history; D014481:United States