Mouth Breathing and a Narrow Upper Jaw: What an Airway Evaluation Looks At

Peak Family Dentistry • Patient Education

Quick answer: A narrow palate and mouth breathing are linked in both directions: chronic mouth breathing can hold back upper jaw growth, and a narrow upper jaw can restrict nasal airflow. An airway evaluation looks at breathing history, jaw and palate width (often with imaging), tongue posture and tongue-tie, and bite. It identifies risk factors and guides next steps. It does not diagnose sleep apnea, which requires a physician-ordered sleep study. At Peak Family Dentistry in Albuquerque, NM, Dr. Billie Adams evaluates these areas for both children and adults.

This article is for general education and isn't a substitute for an in-person evaluation.

Why a Narrow Palate and Mouth Breathing Often Appear Together

The upper jaw forms the floor of the nose, so its width affects nasal airflow. A systematic review of the research describes how a narrow upper jaw often comes with a high, narrow palate and a posterior crossbite, and how that shape elevates the nasal floor and reduces nasal cavity volume. The same review describes a bidirectional relationship: chronic mouth breathing can alter muscle balance and inhibit transverse upper jaw growth, while a narrow jaw further limits nasal airflow and keeps the obstruction going.

The numbers show how common the overlap is. The review reports that up to 47% of children with nasal breathing problems have a constricted upper jaw, which itself affects roughly 2.7% to 23.3% of people under 18. It also notes that a high-arched palate and upper jaw constriction are recognized risk factors for upper-airway narrowing, even without enlarged tonsils or adenoids.

These are patterns across groups. They don't tell you which came first in one person, which is a reason to get evaluated instead of guessing.

What an Airway Evaluation Looks At

At Peak Family Dentistry, an airway evaluation reviews four areas. The table below explains what each one covers and why it matters.

Some findings point outside dentistry. Enlarged tonsils or chronic nasal congestion are medical issues, so concerns there typically lead to a referral to a physician or ENT.

What Research-Based Screening Looks For in Children

A pediatric screening tool called FAIREST-6 shows what clinicians look for. In a cross-sectional study of 96 children in mixed dentition, researchers identified six exam findings with the strongest links to sleep disturbance scores:

• Mouth breathing, defined as being unable to keep breathing through the nose with lips sealed for more than three minutes
• Mentalis strain, or visible chin tension to keep the lips closed
• Tonsillar hypertrophy
• Ankyloglossia (tongue-tie)
• Dental wear
• A narrow palate

The researchers built the tool to help clinicians identify children at risk of sleep-disordered breathing earlier. It is a screening aid for children, not a diagnosis, and a finding means a closer look is warranted. These are research examples, not a list of what any single office uses.

How Evaluation and Treatment Differ for Children and Adults

For children, the focus is on the growth window. Peak Family Dentistry's pediatric airway management and early orthodontics pages describe guiding arch development while the jaw is still growing.

For adults, the jaw has finished growing, so options differ. Adults whose palate seam has fused may be evaluated for MARPE, or for coordinated care with TMJ and sleep apnea treatment. Our airway orthodontics page explains this airway-first approach.

What an Evaluation Can and Can't Tell You

An evaluation can identify structural contributors, such as a narrow palate or restricted tongue movement, and decide whether treatment, monitoring, or a referral makes sense. It can also flag possible sleep concerns for follow-up.

It can't diagnose obstructive sleep apnea. That requires a sleep study ordered through a physician, and sleep apnea treatment decisions are made with that physician. Peak Family Dentistry's sleep apnea page covers the oral appliance options Dr. Adams provides. An evaluation also can't promise results, because outcomes of any treatment vary from patient to patient.

Questions to Ask Before an Airway Evaluation

• What will be examined, and will imaging be part of it?
• Is my tongue-tie status being checked as well?
• If you find a narrow palate, what are my options at my age?
• Which findings, if any, would you refer to an ENT or sleep physician?
• What happens if I decide to monitor and not treat?

Frequently Asked Questions

Does an airway evaluation involve a sleep test?

Not in the dental office. It usually involves a history, an exam, and imaging where appropriate. If a sleep disorder is suspected, a physician orders the sleep study.

At what age can an airway evaluation be done?

Airway-related findings can be evaluated at any age. In children, earlier evaluation leaves more options while the jaw is still growing.

Getting Your Airway Evaluated

If you or your child breathes through the mouth, snores, or has a narrow-looking upper jaw, an evaluation can show what's contributing. To talk with Dr. Adams, request a consultation or call (505) 293-2211.

References

1. Oh JS, Zaghi S, Peterson C, Law CS, Silva D, Yoon AJ. Determinants of Sleep-Disordered Breathing During the Mixed Dentition: Development of a Functional Airway Evaluation Screening Tool (FAIREST-6). Pediatric Dentistry. 2021;43(4):262–272. https://www.ingentaconnect.com/contentone/aapd/pd/2021/00000043/00000004/art00004
2. Relationship Between Maxillary Transverse Deficiency and Respiratory Problems: A Systematic Review of the Effectiveness of Devices over the Past Decade. PMC, National Library of Medicine. https://pmc.ncbi.nlm.nih.gov/articles/PMC12733806/