The evolution of dental hygiene, or how we got where we are today.
D003756:Dental Hygienists / Q000639:trends*; D003777:Dental Prophylaxis; D006267:Health Education, Dental / Q000639:trends; D006285:Health Planning / Q000639:trends*; D006301:Health Services Needs and Demand / Q000639:trends*; D006801:Humans; D010510:Periodontal Diseases / Q000628:therapy