Airway and orthodontics: how to evaluate what you are told

What airway-aware orthodontics means, and what it does not

An airway-aware orthodontist looks beyond tooth alignment to the structures that shape the space behind the nose and mouth: the width of the upper jaw, the position of the lower jaw, the height of the palate, the size of the tonsils and adenoids visible on examination, tongue posture and habitual mouth breathing. Those findings are recorded as part of the diagnosis, not treated as an afterthought.

It does not mean that braces, aligners or expanders are a treatment for sleep apnea. Obstructive sleep apnea is a medical diagnosis, made by a physician on the basis of a sleep study, and its first-line management in children is medical or surgical. The American Association of Orthodontists set this out in its 2019 white paper: orthodontists are well placed to recognize signs and to contribute to a plan, and they do so alongside physicians rather than in place of them.

The useful middle ground is this. Where a child has a narrow upper jaw or a lower jaw set well back, correcting that growth pattern is orthodontic work with its own justification, and the research summarized below shows it can also change how the airway functions. A provider who explains both the orthodontic reason and the breathing dimension, and who involves the right physicians, is practising the way the evidence supports.

Findings that may warrant an airway conversation

Parents usually raise the subject because of something they see at home, and orthodontists usually raise it because of something they see in the mouth. Both sets of observations matter, and neither is a diagnosis on its own.

• Habitual mouth breathing during the day, or lips apart at rest
• Snoring, noisy breathing, restless sleep, unusual sleeping positions or daytime tiredness
• A narrow or high-arched palate, a crossbite of the back teeth, or crowding that reflects a small upper jaw
• A lower jaw that sits well back, with prominent upper front teeth
• Enlarged tonsils visible on examination, or a history of frequent ear, nose and throat infections
• A long, narrow face with a tendency for the mouth to hang open

The American Academy of Pediatrics recommends that every child be asked about snoring at routine visits, and that a child who snores and shows other signs be assessed with a sleep study or referred to a specialist. If your child has several of the findings above, ask both the family physician and the orthodontist about them. The two conversations should connect.

Who diagnoses what

Clear roles protect you from being sold a solution before there is a diagnosis. In British Columbia, as elsewhere, the division is consistent.

An orthodontist can and should screen, record findings and refer. An orthodontist should not tell you that your child has sleep apnea without a medical diagnosis, and should not tell you that an appliance will resolve a condition that has not been diagnosed. Equally, a physician who dismisses the shape of the jaws as irrelevant is leaving part of the picture out. Ask each professional how they work with the other.

What the peer-reviewed research supports

This is an area where families deserve specifics rather than vague reassurance in either direction, so here is what the published evidence says.

Expansion of a narrow upper jaw. A 2017 systematic review and meta-analysis in The Laryngoscope pooled 17 studies of 314 children, average age about seven and a half, who had a narrow or high-arched palate and diagnosed obstructive sleep apnea. After rapid maxillary expansion, the average apnea-hypopnea index fell by roughly 70 percent and the lowest recorded oxygen saturation improved, with the effect holding in the smaller group followed for more than three years. Children whose tonsils were small or had already been removed improved more than children with large tonsils, which is itself an argument for the medical and orthodontic assessments working together.

Guiding the lower jaw forward. A 2016 systematic review in Sleep Medicine Reviews, with authors from the University of Montreal and the University of British Columbia, examined functional appliances that hold the lower jaw forward in growing children, together with expansion. The authors concluded that these treatments may be effective in managing paediatric snoring and obstructive sleep apnea, while noting that the number of well-designed studies is still small and that larger trials are needed.

The professional consensus. The American Association of Orthodontists white paper reviewed the same body of evidence and concluded that orthodontists have a legitimate screening and treatment role within a medical framework, and that claims of cure should be avoided. That is the position this guide takes as well.

Two cautions keep the reading honest. The clearest results are in children with a specific anatomical finding, a narrow upper jaw, and a confirmed diagnosis. They do not mean that every child who snores needs an expander, or that expansion replaces the assessment a physician provides. And most children in these studies were treated because they needed orthodontic correction anyway; the breathing benefit was measured alongside the orthodontic one.

How growth modification fits, and when

Where a jaw-growth pattern is part of the picture, the orthodontic options are the same ones a provider would discuss for the bite alone. Our guide to expansion and early treatment covers them in detail; in brief, a provider may propose an expander to widen a narrow upper jaw, a twin block or similar functional appliance to guide a retruded lower jaw forward, or aligner-based versions of both, such as Invisalign First for arch development in younger children and Invisalign with mandibular advancement for growing teenagers. Which appliance, and whether expansion is done with a fixed expander or built into the functional appliance, is a case-by-case decision that depends on the diagnosis.

Timing matters because these appliances work with growth. The Canadian Association of Orthodontists recommends a first assessment at around age seven, when the first permanent molars and incisors have arrived and the pattern of jaw growth can be read. That is the assessment, not a commitment to treatment; many children are simply monitored. Where a breathing concern exists, the age-seven visit is the natural point to raise it, because the window for changing jaw width and position is widest before the adolescent growth spurt.

A well-run early treatment plan states its orthodontic goals, records the airway findings at the start, involves a physician where indicated, and re-examines the findings when the appliance comes out. If a provider cannot tell you what will be measured and when, ask.

Adults: a different conversation

In adults, jaw growth is complete, so the tools change. Braces and aligners do not widen an adult's upper jaw in the way an expander widens a child's, and they are not a treatment for adult sleep apnea.

Three adult situations come up. First, an adult with a significant jaw discrepancy and diagnosed sleep apnea may be a candidate for surgery that advances the jaws, which is a medical and surgical decision planned with an oral and maxillofacial surgeon and a sleep physician; our guide to jaw surgery explains how that team works. Second, an adult who snores and wants an oral appliance that holds the lower jaw forward at night should be assessed by a sleep physician and fitted through a dentist experienced in those appliances; holding the jaw forward every night can gradually change the bite, which is one reason the fitting should be supervised and reviewed. Third, an adult may simply want the breathing dimension considered as part of ordinary orthodontic planning, for example where extractions or arch width are being discussed, and that is a reasonable request.

One point of confusion is worth clearing up: Invisalign with mandibular advancement is a growth-modification appliance for preteens and teenagers. It is not a retainer and it is not a snoring appliance for adults.

How to evaluate a provider who raises airway

Because this subject is important and also easy to overstate, the way a provider talks about it tells you a great deal. Signs of a careful provider include:

• They separate what they can assess from what a physician must diagnose, and they refer
• They can name the specific findings in your child's mouth that raised the question
• They explain the orthodontic reason for the plan first, and the breathing dimension second
• They can point to the research and describe its limits without either dismissing it or over-promising
• They record airway findings at the start and plan to re-examine them

Reasons for caution include a diagnosis of sleep apnea offered without a sleep study, a promise that an appliance will cure snoring, mouth breathing or attention difficulties, a plan that cannot be explained in terms of the jaws and bite, and pressure to start quickly. None of these is a reason to abandon the subject; each is a reason to get a second opinion. Our guide to the questions to ask at a consultation applies here as well.

For deeper, parent-oriented education on breathing and jaw development, written for the whole country rather than one city, see airwayorthodontics.ca.