Rapid Palatal Expander
Also written as: RPE — Rapid Palatal Expander
A fixed orthodontic appliance that applies transverse forces to the midpalatal suture to widen a constricted maxillary arch.
Full Definition
A rapid palatal expander (RPE) is an intraoral device cemented to the upper posterior teeth, used to treat maxillary transverse deficiency (crossbite or arch constriction) by gradually widening the palate. It works by applying controlled lateral forces to separate the midpalatal suture before it fuses, typically in patients under 15–18 years of age. The device requires activation by turning a key-like mechanism in a central screw. Editors should be aware that the abbreviation RPE is standard in clinical and research texts, but must be defined on first use in general-audience documents. 'Palatal' is preferred over 'palatel,' a common misspelling.
Usage
Usage note: Abbreviate as RPE after first full use. 'Palatal' not 'palatel' or 'palatial.' Do not hyphenate when used attributively: 'rapid palatal expander therapy.'
In Context
- "A rapid palatal expander was fitted to correct the posterior crossbite before brackets were placed." — Orthodontic treatment plan
- "The RPE was activated twice daily for three weeks to achieve the desired arch width." — Clinical case notes