Functional Appliance
A removable or fixed orthodontic device that harnesses the forces of the orofacial musculature and mandibular posture to modify skeletal growth.
Full Definition
Functional appliances are a class of dentofacial orthopedic devices designed to redirect growth by positioning the mandible or modifying muscle function rather than exerting direct mechanical forces on teeth. They include both removable designs (e.g., Twin Block, Activator, Bionator, Frankel) and fixed designs (e.g., Herbst appliance, MARA). Functional appliances are most effective during periods of active skeletal growth and are used primarily to treat Class II skeletal discrepancies. Editors should note that 'functional appliance' is a broad category term; specific devices within this category should be identified by their proper eponymous names, which are capitalized.
Usage
Usage note: Lowercase as a category term. Individual appliance names (Twin Block, Herbst, Bionator) are capitalized as eponyms. Do not conflate with 'myofunctional appliance,' which targets oral musculature specifically.
In Context
- "A functional appliance was selected over fixed appliances given the patient's residual skeletal growth potential." — Treatment-planning note
- "The review compared the efficacy of removable versus fixed functional appliances in correcting Class II discrepancies." — Systematic review abstract