Loose, usually removable intra-oral devices which alter the muscle forces against the teeth and craniofacial skeleton. These are dynamic appliances which depend on altered neuromuscular action to effect bony growth and occlusal development. They are usually used in mixed dentition to treat pediatric malocclusions. (ADA, 1992)

Synonyms: Functional Orthodontic Appliances, Function Regulator, Frankel, Appliance, Bimler, Herbst Appliance, Bimler Appliance, Orthodontic Appliance, Functional, Regulator, Frankel Function, Appliance, Functional Orthodontic, Kinetors, Functional Orthodontic Appliance, Appliances, Functional Orthodontic, Frankel Function Regulator, Appliance, Herbst, Orthodontic Appliances, Functional, Kinetor