title: An orthodontic challenge.
mesh_terms: D002648:Child; D004200:Diseases in Twins; D004955:Esthetics, Dental; D005145:Face / Q000033:anatomy & histology; D005260:Female; D006801:Humans; D008310:Malocclusion / Q000628:therapy*; D009967:Orthodontic Appliances; D012690:Serial Extraction