The Spahl split vertical appliance.
Spahl
T J
TJ
D006801:Humans; D008310:Malocclusion / Q000628:therapy*; D008334:Mandible; D016382:Orthodontic Appliance Design; D017289:Orthodontic Appliances, Functional; D009968:Orthodontic Appliances, Removable; D009971:Orthodontics, Corrective / Q000379:methods*; D014078:Tooth Eruption