Fränkel Appliance
Pronunciation: FREN-kel
A removable functional appliance designed to modify perioral and buccal muscular activity to stimulate skeletal and dentoalveolar changes.
Full Definition
The Fränkel appliance, also called the Function Regulator (FR), was developed by Rolf Fränkel and works primarily by repositioning the soft-tissue environment rather than applying direct mechanical forces to the teeth. It uses acrylic shields placed in the buccal and labial vestibules to eliminate abnormal muscle pressure, theoretically allowing the jaws and alveolar processes to develop more freely. Several versions exist (FR-I, FR-II, FR-III), each targeting different malocclusion types. Editors must be aware of the correct diacritic on 'Fränkel' and the preferred spelling 'Function Regulator' when the abbreviation FR is used.
Usage
Usage note: Retain the umlaut (ä) in 'Fränkel' in all formal editorial contexts. When abbreviated to FR, specify which variant (FR-I, FR-II, FR-III) is being discussed.
In Context
- "The Fränkel appliance was prescribed to address the transverse deficiency in the mixed dentition." — Orthodontic case report
- "Editors should preserve the umlaut in 'Fränkel' and not substitute 'Frankel' in formal publications." — Journal style guide note