A narrow upper jaw affects not only the aesthetics of the smile, but also the bite, breathing and even the quality of sleep. Fortunately, there is now an effective, safe and well-established solution: the Hyrax appliance, which performs expansion of the palate or upper jaw – whether in childhood or in adulthood.
In many children and adults the upper jaw is narrower than the lower one. This can cause, for example:
If the upper jaw is narrow, it is not just an aesthetic issue: it can affect breathing, chewing and even the development of the face.
In childhood the bones are still flexible, and between the two halves of the palate there is a growth suture (the midpalatal suture), which responds well to expansion up to about 15 years of age.
This is when the Hyrax appliance can be used; the orthodontic specialist fixes it to the upper teeth. With the small screw in the middle, we expand the palate very gently each day. The procedure can be carried out at home, and the expansion itself takes about 2 to 3 weeks.
What happens during this time?
Several studies have confirmed that after Hyrax expansion, airflow in the nasal cavity and ventilation of the middle ear may also improve (e.g. Pirelli et al., Sleep Med 2021; Article).
If palatal expansion does not take place in childhood, the suture fuses into bone once growth is complete.
In such cases, conventional Hyrax expansion alone is no longer effective enough, because the bone cannot separate – the appliance would only tip the teeth.
However, this does not mean that it is too late.
Even in adulthood there is a possibility to expand the upper jaw, only with surgical support: this is what we call SARME (Surgically Assisted Rapid Maxillary Expansion).
You can read about this in detail here:
SARME – Surgically Assisted Rapid Maxillary Expansion
For adult expansion we often use a Hybrid Hyrax appliance: this is an enhanced version of the conventional Hyrax that is anchored to the bone with mini-implants (small titanium screws).
This way, the expansion force moves not only the teeth but the bone itself – more safely and more precisely.
If the ossification is already advanced, the oral surgeon loosens the bone suture with a small procedure (SARME), and then the orthodontist activates the expander.
This combination is the gentlest and most stable solution in adulthood.
Result:
Is the expansion painful?
No. The expansion with the Hyrax appliance may cause a mild sensation of pressure, but you get used to it within a few days. Most patients describe it as strange rather than painful.
How long does the treatment take?
The active phase of expansion lasts 2 to 4 weeks, and then, for stabilisation, the appliance stays in place for 3 to 6 months so that the new bone can consolidate.
Is the Hyrax visible from the outside?
No. The appliance is fixed to the palate and is practically unnoticeable from the outside.
Can it improve nasal breathing?
Yes. According to several studies, after expansion the cross-section of the nasal passages increases, making nasal breathing easier (Compadretti et al., Am J Orthod Dentofacial Orthop 2006; Article).
Many people first turn to an orthodontist for aesthetic reasons, but expansion also brings functional benefits:
Proper nasal breathing also plays a role in the development of the teeth, the jaw and posture — which is why it is especially important to treat a narrow upper jaw in time.
If you notice that:
At the Foxxi clinic, with a digital 3D scanner and X-ray, we can precisely assess the extent of the narrowing and which form of expansion (Hyrax, Hybrid Hyrax, SARME) is the most ideal for you.
The Hyrax appliance and palatal expansion improve not only the alignment of the teeth, but can also have a positive effect on breathing, sleep and the harmony of the face.
In childhood it can be treated quickly and effectively, and in adulthood it can be carried out just as successfully with surgical support.
This article was prepared by the professional team of Foxxi Buda Orthodontics.
Professional reviewers: Dr. Magyar Dominika Ph.D. and Dr. Pulay Zoltán – orthodontic specialists
The content of the article is based on reliable, professional sources, including relevant studies from the PubMed database.
A few selected literature references / further reading
Types of Braces – Find the One That’s Best for You!
The Orthodontic Treatment Process Step by Step
Orthodontics: How to Live in Harmony with Your Braces
Children’s Orthodontics with Invisalign First Clear Aligners
Underbite: More Than Just an Aesthetic Concern
Impacted Canines: A Hidden Problem with a Visible Solution at Foxxi
