title: Four decades of change.
authors.forename: N H
authors.initials: NH
authors.lastname: Olsen
mesh_terms: D002648:Child; D003729:Dental Care / Q000295:instrumentation / Q000379:methods / Q000639:trends*; D004497:Education, Dental / Q000639:trends*; D006801:Humans; D010377:Pediatric Dentistry / Q000193:education / Q000639:trends*; D014481:United States