Widening the upper jaw: when braces alone are not enough
If the upper jaw is too narrow, braces alone may not be enough: they move teeth within the existing arch. Expansion appliances work on the jaw itself.
Key points
- Braces move teeth within the existing dental arch; they do not widen the jaw itself.
- Where the upper jaw is narrow, expansion addresses the cause rather than the consequence.
- Indications: crossbite, marked crowding, insufficient space for permanent teeth, an upper jaw noticeably narrower than the lower.
- The appliance is fixed to the upper jaw and opens gradually by means of a screw.
- The earlier the problem is identified — usually in childhood or adolescence — the easier treatment is.
When expansion is needed
An orthodontist recommends widening the upper jaw when braces alone will not be enough. The main indications are a narrow upper jaw, a crossbite, marked crowding, insufficient space for permanent teeth to erupt, and an upper jaw significantly narrower than the lower one.
Expansion may also be a preparatory stage before braces — creating the space in which teeth can then be aligned correctly.
How the appliance works
The appliance is fixed to the upper jaw and carries an expansion screw. Activated gradually, it opens the palatal suture, the width of the upper jaw increases and space appears for the teeth to sit correctly.
Expansion happens in small steps on a schedule set by the clinician, not all at once.
Appliances used for expansion
Hyrax is anchored to the teeth and is used mainly in childhood and adolescence, while the palatal suture has not finished ossifying.
The clinic also uses other expansion systems, including MSE. Which one suits a given case is decided by the orthodontist after examination and diagnostics.
What expansion achieves
After expansion there is space for the teeth, crowding is reduced and a crossbite can be corrected.
If difficult nasal breathing was caused specifically by a narrow upper jaw, breathing may improve. This is not a universal effect: the causes of impaired nasal breathing vary and must be assessed by a clinician.
Subsequent treatment with braces is more effective and the result more stable, because the teeth sit in a jaw of adequate width.
Frequently asked questions
Why can braces alone not do the job?
A brace system moves teeth within the existing dental arch. If the jaw itself is narrow, there is not enough space for correct tooth positions and the result is less stable.
At what age is expansion easier?
Usually in childhood and adolescence, while the palatal suture has not finished ossifying. Whether and how expansion is possible in adult patients is assessed individually by the orthodontist.
Which appliance will the doctor choose?
The clinic uses several expansion systems, including Hyrax and MSE. The choice depends on the clinical situation and diagnostic findings, so the orthodontist makes it at the appointment.
Will nasal breathing improve?
If the difficulty was linked specifically to a narrow upper jaw, it may. The causes of impaired nasal breathing vary, so assessment has to be individual.
How long does the expansion stage take?
Timing depends on the starting situation and the appliance chosen. The active phase may take several weeks, followed by a period of holding the result.
Sources used to prepare this guide
Content updated: 2026-07-31