The Harvold activator. Simplified construction and use.
D000202:Activator Appliances; D000293:Adolescent; D004867:Equipment Design; D005260:Female; D006801:Humans; D008310:Malocclusion / Q000628:therapy; D009968:Orthodontic Appliances, Removable; D014087:Tooth Movement Techniques / Q000295:instrumentation / Q000379:methods