Oral Function in Children: What It Is and Why It Matters for Breathing, Sleep and Development

You may have heard someone mention that oral function is important.

Maybe it came up in a podcast. Maybe a friend mentioned mouth breathing. Maybe you saw something about jaw growth or tongue posture online.

And you thought: But what does that actually mean?

Let's unpack it 👇

What Is Oral Function?

Oral function is how the muscles in the mouth and face work to:

• Breathe

• Chew

• Swallow

• Speak

• Rest

That’s it. It’s really not as niche as it sounds. It’s simply how your child uses the muscles of their mouth and face every single day. And those muscles are active far more often than we realise.

Why Does Oral Function Matter?

The way your child uses their muscles shapes their facial appearance, their jaw growth, the position of their teeth, and the size of their upper airway.

The upper airway includes:

• The nose

• The sinuses

• The soft tissues at the top of the throat

So we’re not just talking about teeth. We’re talking about growth, breathing and appearance. There’s an analogy often used to explain this:

The bones in your child’s face are like clay, and the muscles are like sculptors.

In childhood, that 'clay' is still developing. Every time your child breathes, swallows, chews, or rests their tongue, the muscles apply gentle, repeated pressure. Over time, those repeated patterns contribute to shaping the bones.

The shape and function of a child's face doesn't just influence their mouth, it connects to the health of their whole body.

1. Sleep

The way the jaw develops affects the space available for the upper airway. If the airway is smaller or less stable, breathing during sleep can become more effortful and sleep quality is reduced. Sleep quality affects everything — mood, learning, growth, immune function. So when we talk about oral function, we’re often indirectly talking about sleep.

2. Regulation & Nervous System

Breathing patterns influence the nervous system. Nasal breathing supports a calmer, more regulated state ('rest and digest'). Chronic mouth breathing can keep the body in a more activated state ('flight or flight').

3. Eating Ability

Chewing isn’t just about breaking food down. It’s muscle development, jaw stimulation and a lot of coordination. Limited chewing ability or avoidance of tougher textures can reduce the muscular input needed for optimal jaw growth.

4. Posture

The tongue is a postural muscle. Where the tongue rests influences the position of the jaw, head and neck. And head posture influences overall body alignment. Forward head posture often shows up alongside oral dysfunction and mouth breathing.

What Is Oral Dysfunction?

Oral dysfunction happens when the muscles in the mouth and face aren’t working together in the way they are designed to achieve all of these functions.

When dysfunction is present:

• Some muscles can be overused, tense, and far stronger than they need to be

• Other muscles may be underused and weak

• The body compensates

You may also hear the more clinical term: orofacial myofunctional disorders.

What Does Oral Dysfunction Look Like?

Signs of oral dysfunction in children:

• Difficulty chewing certain foods

• Drooling outside of active teething

• Facial or jaw pain

• Limited tongue movement

• A low resting tongue position

• The tongue pushing or thrusting forward during speech or swallowing

• Persistent open mouth posture

• Snoring or restless sleep

What Causes Oral Dysfunction?

There isn’t usually one single cause. Oral dysfunction tends to develop from a combination of influences over time.

Some contributing factors can include:

• General posture

• A high, narrow palate

• Limited chewing variety

• Long-term sucking habits

• Extended use of dummies or bottles

• Mouth breathing

• Ongoing pain or muscle tension

• A smaller jaw structure

• Congenital conditions

• Injury

• Low muscle tone

• Tongue, lip, or cheek ties

And here’s where it becomes nuanced. Some of these factors can be both causes and effects.

For example:

• Mouth breathing can influence jaw development — but a smaller jaw can also make nasal breathing more difficult.

• Low muscle tone can affect tongue posture — but poor tongue posture can further weaken muscle patterns over time.

The relationships between cause and effect are often circular in nature. It can be difficult to pinpoint exactly what started the cycle of dysfunction in the first place.

Why Haven’t You Heard About This Before?

The study of oral function isn’t new. Fields such as orofacial myology and dental sleep medicine have decades of research behind them. There is extensive literature exploring the relationship between muscle function, airway development, sleep quality, and craniofacial growth.

These areas are well established within certain professional communities. However, they are not typically taught in depth as part of standard undergraduate medical, dental, or allied health education.

Which means that unless a professional takes a specific interest in airway, muscle function, or developmental growth patterns, and chooses to pursue additional training, they may not receive education on the importance of oral function in children.

Professionals who work in this space usually do so because they’ve actively extended their education, experience, and clinical lens beyond foundational training.

That’s why you might only hear about oral function from:

• A speech pathologist with orofacial myology training

• A dental professional with additional airway or sleep education

• An orthodontist with an interest in early growth guidance

What Next?

If you feel unsure about where to start, that’s completely understandable. Oral function is simple in principle, but nuanced in practice.

If you’d like a comprehensive explanation of how growth, muscle use, airway, and dental development connect, I teach this in my Foundations for Growing Faces masterclass.

Inside the 45-minute video masterclass, we cover:

• Breathing and sleep
  How nasal breathing supports development, what mouth breathing can look like, and what sleep patterns are worth monitoring.

• Chewing and diet
  Why chewing matters for jaw growth, the role of the modern diet, and how to support chewing in day to day life.

• Habits at home
  Dummies, bottles, cups - what helps, what interferes, and what to prioritise.

• Understanding support pathways
  When home education is enough and when extra support can be helpful.

About The Face Place
The Face Place supports families with early intervention care for children’s oral function and dental health. Led by Oral Health Therapist Melanie Van Schelven, our approach blends clinical insight with family-centered education, helping parents understand why something’s happening and what to do next.

Visit thefaceplaceofm.com.au for more free guides and evidence-based support.