Mouth Breathing in Children: Why It Matters and When to Seek Help

Mouth breathing in children is one of the most common, and most overlooked, health concerns in paediatric care. Parents across Cooranbong, Lake Macquarie, Morisset and the Hunter Valley increasingly ask about it because they've noticed their child sleeping with their mouth open, snoring, or having a persistently open mouth posture during the day. These are not minor quirks. Chronic mouth breathing in children can have significant effects on dental development, facial growth, sleep quality, concentration and speech. This article explains why it matters, how to recognise it, and how orofacial myofunctional therapy treats it.

Why is mouth breathing a problem?

The nose is the body's primary air filtration and conditioning system. Nasal breathing warms, humidifies and filters incoming air, and produces nitric oxide, a molecule that plays a key role in immune function and oxygen absorption in the lungs. When a child breathes through the mouth instead, they bypass all of these mechanisms. The consequences compound over time.

Research published in the European Journal of Orthodontics has documented the craniofacial effects of chronic mouth breathing: the palate develops narrowly and vertically rather than broadly and horizontally, creating insufficient space for the permanent teeth. The result is dental crowding, an increased likelihood of orthodontic intervention, and in many cases a narrowed upper airway that perpetuates the breathing problem. Children who breathe through their mouths chronically are also more likely to have disturbed sleep, reduced oxygen saturation during sleep, and the daytime consequences that follow: poor concentration, behaviour difficulties, bedwetting and fatigue.

Signs your child may be mouth breathing

The most obvious sign is an open mouth posture, with the mouth resting open during the day or during sleep. Other signs include snoring or noisy breathing during sleep, restless sleep and frequent waking, dark circles under the eyes unrelated to screen time, a long and narrow facial profile (adenoid facies), crowded teeth or a narrow upper jaw, frequent ear infections, tonsil or adenoid issues, and speech sound difficulties particularly with sounds that require the tongue tip to be elevated.

What causes chronic mouth breathing in children?

The causes are usually multiple and interacting. Tongue tie is one of the most common contributing factors. When the tongue cannot rest fully on the roof of the mouth, the mouth tends to fall open to accommodate it. Enlarged tonsils and adenoids are another major cause, physically obstructing the nasal airway. Allergic rhinitis, chronic nasal congestion, and structural nasal issues also contribute. In many cases, even after the physical obstruction is addressed, the habit pattern of mouth breathing persists because it has become the child's default neurological programme.

How is mouth breathing treated?

Treatment depends on the cause. Medical causes (enlarged tonsils, adenoids, allergy) should be addressed first through the appropriate professional (ENT specialist, paediatrician or GP). Tongue tie, if present, should be assessed and managed. Once physical obstructions are addressed, orofacial myofunctional therapy provides the essential next step: retraining the tongue to rest in the correct position on the palate and reestablishing nasal breathing as the default pattern. Without this retraining, the breathing habit almost always persists even after medical intervention. Watagan Health Hub works closely with Watagan Dental to provide integrated assessment and treatment for children with mouth breathing and associated orofacial concerns.

Mouth breathing treatment in Cooranbong and Lake Macquarie

Watagan Health Hub is the only provider of orofacial myofunctional therapy in Lake Macquarie and the Hunter Valley, integrated with Watagan Dental for coordinated dental and allied health care. To learn more or register your interest, visit our myofunctional therapy Hunter Valley page, or read our post on tongue tie and myofunctional therapy. Watagan Health Hub is your local allied health Cooranbong clinic.