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MARA applianceresearched

Quick facts

FieldValue
IDOA-0136
Typefunctional
Categoryfunctional
Fixed/removablefixed (cemented SS crowns)
Primary functionmandibular advancement; Class II correction
Malocclusion targetClass II; overjet; retrognathic mandible
InventorIra Voudouris (original concept); TP Orthodontics (MARA brand)
First year1990s
Periodmodern
Statuscurrent
Compliance requiredno
Uses TADsno

Overview

The MARA (Mandibular Anterior Repositioning Appliance) is a fixed functional appliance that repositions the mandible forward without patient cooperation. It consists of stainless steel crowns cemented to the upper and lower first molars, with horizontal arms extending from the lower molar crowns. When the patient closes, these arms engage the upper crown and force the mandible to function in a forward (Class I) position. Unlike removable functional appliances, the MARA is always active — regardless of patient compliance — and allows simultaneous placement of fixed braces, enabling a one-phase comprehensive treatment approach. It can also be fabricated with an integrated RPE screw for combined Class II + transverse correction.

Clinical & technical

Mechanism of action

The lower elbow arms extend anterolaterally from the lower molar crowns. When the patient closes, the arm contacts the distal or buccal surface of the upper first molar crown, acting as a cam stop that prevents the mandible from retracting to its natural Class II relationship. The patient must function with the mandible in the postured position at all times. Over 9–18 months, adaptive condylar remodeling (posterior-superior condylar bone apposition), glenoid fossa remodeling, and dental changes produce a stable forward mandibular position. Average Class I correction: 9–12 months of active wear. Because it's always on, the cumulative adaptation stimulus is maximized compared to nighttime-only removable appliances.

Indications & case selection

Class II malocclusion in growing patients requiring mandibular advancement; cases where compliance is a concern (MARA removes compliance variable entirely); patients who want to complete treatment faster (simultaneous braces + MARA reduces total treatment time); Class II with transverse deficiency (MARA + RPE variant); practices that prefer fixed functional over removable for all Class II cases. MARA is the fixed functional appliance of choice for many growth-guidance oriented practices in the US.

Contraindications & limitations

Does not treat skeletal Class II beyond functional correction — severe mandibular retrognathia or large AP discrepancy may require orthognathic surgery. The SS crowns cover the first molars and temporarily alter the occlusion — can cause initial temporomandibular discomfort. Requires precise crown fit — poorly fitting crowns produce uneven forces. If the arm engagement plane is not set correctly, the MARA will not engage on closure. Some patients experience initial speech difficulty. Can cause mild gingival irritation around crowns if hygiene is poor.

Design & fabrication

Components & materials

total)

active cam elements

contact

connection bar

(allowing full fixed braces)

Lab fabrication notes

Crown fit is the most critical variable — a crown that rocks or gaps at the gingival margin will not anchor the MARA correctly. Crown should be crimp-fitted and adapted carefully from properly trimmed models. The arm extension must be precisely calibrated to the prescribed advancement distance. For the 3D/digital MARA, digital scanning and milling enables more precise crown adaptation and arm geometry. The MARA with expansion incorporates an RPE screw into the upper arch connection — the screw housing must be properly oriented and the connection framework must be rigid. These are among CFL's most expensive appliances, reflecting the complexity.

Common variants & modifications

check CFL).

rod-and-tube mechanism; see Frankel appliance.

functional; compliance-dependent.

archwire).

Also known as

Sources

Ortho](https://ivanovortho.com/what-is-a-mara-appliance/)

Ortho](https://www.mcdermottortho.com/mara-appliance/)

Ordont](https://ordont.specialtyappliances.com/product/mara/)

Orthodontics](https://www.jorgensenorthodontics.com/blog/what-is-the-mara-appliance)

Research log

fabrication, business notes.