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Haas expanderstub

Quick facts

FieldValue
IDOA-0349
Typeexpander
Categoryexpander
Fixed/removablefixed
Primary functionrapid maxillary expansion; mid-palatal suture opening
Malocclusion targetmaxillary constriction; crossbite; crowding in growing patients
InventorHaas
First year1961
Periodmodern
Statuscurrent
Uses TADsno

Overview

Tooth- and tissue-borne rapid palatal expander. A central expansion screw is embedded in acrylic pads that contact the palatal mucosa; molar bands provide additional anchorage. Forces are distributed to both teeth and palatal tissue to open the mid-palatal suture and widen the maxillary arch. Preferred in growing patients with narrow maxilla or posterior crossbite.

Distinguished from the Hyrax by its acrylic palatal pads (tissue contact). Variants include sectional screw and 3D-printed versions.

Clinical & technical

Mechanism of action

To research.

Indications & case selection

To research.

Contraindications & limitations

To research.

Design & fabrication

Components & materials

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Lab fabrication notes

To research.

Common variants & modifications

Also known as

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