What Is an Open Bite in a Child and Why Does It Matter?
If your child’s front teeth do not meet when they bite down, you may be looking at an open bite. It can affect biting, speech and jaw development, but early assessment often gives families more non-surgical, appliance-based options suited to the individual case.
Key Takeaways
- An open bite means the upper and lower teeth do not meet properly when your child bites down.
- Common causes include thumb sucking, prolonged dummy use, tongue thrusting and mouth breathing.
- Early assessment can help identify whether the issue is dental, habit-related or linked to jaw growth.
- Many children can be helped with habit support, speech therapy when needed or interceptive orthodontic appliances.
- A specialist orthodontic review around age seven gives you clearer guidance before growth patterns become harder to influence.
About the Author
I’m Dr Nick, a Specialist Orthodontist based in Brisbane with over 30 years of experience and more than 11,500 patients treated, including many children with open bite concerns at different stages of development. In this guide, I’ll walk you through the causes, signs and treatment options so you can feel more confident about what to do next.
Understanding Open Bite in Children
An open bite is a type of malocclusion, which means the upper and lower teeth do not line up as they should. When a child with an open bite bites together, a gap remains instead of the teeth meeting evenly.
We usually describe open bites in two main ways:
- Anterior open bite: This is the most common type. The back teeth meet, but the front teeth do not touch, leaving a visible gap at the front of the mouth.
- Posterior open bite: This is less common. The front teeth meet, but the back chewing teeth do not come together properly.
International research published in a scientific review on open bite prevalence has reported anterior open bite rates of around 17% to 18% in children in the mixed dentition stage, when they have a mix of baby and adult teeth. This is included as international context only, not as an Australian prevalence figure, because local rates can differ by population, age, habits and study method.
The same review found the rate can be higher in children with ongoing non-nutritive sucking habits, such as thumb sucking or prolonged dummy use. That is why early assessment matters: the sooner we understand what is driving the bite, the easier it is to choose the right next step.
Dental vs Skeletal Open Bites in Children
When I assess a child with an open bite, one of the first questions is whether the issue is mainly dental or skeletal. That distinction matters because it changes the treatment plan.
- Dental open bites: These are mainly related to the teeth and the bone directly around them. The jaw structure may be balanced, but the teeth have not erupted into the right position, often because a habit such as thumb sucking, dummy use or tongue thrusting has been getting in the way.
- Skeletal open bites: These are linked to the way the facial bones and jaws are growing. In some children, the upper jaw grows downward at the back, and the lower jaw rotates down and back. This can increase the vertical gap between the teeth.
| Feature | Dental Open Bite | Skeletal Open Bite |
|---|---|---|
| Main cause | Habits such as thumb sucking, dummy use or tongue thrusting | Jaw growth pattern |
| Jaw structure | Often balanced | More vertical growth pattern |
| Facial appearance | Usually normal facial proportions | May show increased lower facial height or lips apart at rest |
| Management | Habit support, therapy or targeted interceptive appliances | Growth guidance, orthopaedic appliances or more specialised orthodontic treatment |
Research into paediatric facial growth suggests that vertical growth patterns can be established early in life. By monitoring children during the mixed dentition years, we have a better chance to guide growth while the jaws are still developing.
Common Causes of Open Bite in Children
Several factors can contribute to an open bite. For many children, it comes down to a mix of habits, tongue posture and airway-related breathing patterns.
Thumb Sucking, Dummy Use and Other Habits
Sucking is a normal self-soothing reflex for babies and toddlers. The concern is when the habit continues as the adult teeth begin to come through.
Persistent thumb sucking or prolonged dummy use can place steady pressure on the teeth and developing dental arches. Over time, this can stop the front teeth from erupting fully and may narrow the upper jaw.
The reassuring part is that some habit-related open bites can improve once the habit stops, especially if this happens before the permanent front teeth erupt. If you are unsure whether your child’s habit is affecting their teeth, our guide to crooked teeth in children explains how early habits can shape dental development.
Tongue Thrusting and Oral Muscle Habits
Tongue posture plays a bigger role than many parents realise. Ideally, the tongue rests gently against the roof of the mouth, just behind the front teeth.
In a child with tongue thrusting, the tongue pushes forward between the front teeth during swallowing or at rest. Because we swallow many times throughout the day, that repeated pressure can keep the front teeth apart and make an open bite harder to close.
This is why treatment is not only about moving teeth. If the tongue and lips keep working against the bite, the result may be less stable over time.
Mouth Breathing and Airway Concerns
Airway health can also influence jaw and dental development. If a child often breathes through their mouth because of blocked nasal passages, enlarged tonsils, adenoids or allergies, they may hold the jaw lower and the tongue further forward.
That lower tongue posture can reduce support for the upper jaw. Over time, the upper arch may become narrower, and the back teeth may erupt in a way that encourages the lower jaw to rotate down and back.
In these cases, orthodontic care may need to work alongside a GP, paediatric ENT specialist or speech therapist so the underlying airway issue is addressed as well as the bite.
How an Open Bite Can Affect Your Child Day to Day
An open bite is not just about how the teeth look. It can affect simple daily functions that children rely on for eating, speaking and comfort.
Some common concerns include:
- Biting and chewing difficulties: Children with a front open bite may struggle to bite cleanly into foods such as apples, sandwiches or toast. They may rely more heavily on their back teeth to chew.
- Speech changes: The gap between the teeth can let air escape during speech, which may contribute to a lisp or difficulty with sounds such as “s” and “z”.
- Uneven tooth wear: When the front teeth do not share the load, the back teeth may take more chewing pressure over time.
- Jaw muscle fatigue: Some children compensate for the bite by using their jaw muscles differently, which can contribute to tiredness or discomfort.
Non-Surgical Treatment Options for an Open Bite Child
In growing children, orthodontic treatment can often work with natural growth rather than against it. The right approach depends on the cause, the child’s age and whether the open bite is dental, skeletal or a combination of both.
Early Assessment and Growth Guidance
The mixed dentition stage is an ideal time to assess vertical growth. I recommend that children have their first orthodontic assessment by age seven.
At this age, the first adult molars and incisors have usually started to erupt. That gives us a useful window to see how the bite is developing and whether habits, breathing patterns or jaw growth need attention.
Early monitoring does not mean rushing your child into braces. It simply means we can watch growth carefully and step in at the right time if treatment would make things easier later. You can learn more in our guide to early orthodontic treatment.
Interceptive Appliances for Open Bite
Depending on the cause, we may use different appliances to help guide the bite:
- Fixed palatal cribs: These sit in the upper arch and act as a reminder that stops the thumb or tongue from pushing against the front teeth.
- Bluegrass appliances: These use a small roller near the roof of the mouth to help redirect the tongue away from the front teeth.
- Functional regulators: These removable orthopaedic appliances can help guide jaw growth and reduce unwanted muscle pressure around the arches.
- Bite blocks: These help control the vertical eruption of the back teeth, which may allow the lower jaw to rotate into a more favourable position.
- Clear aligners: In selected growing patients, clear aligners can help manage open bite because the plastic over the biting surfaces can create a gentle bite-block effect.
Long-term clinical research on early treatment stability shows that treating habit-related open bites during the mixed dentition stage can produce stable results when the cause is properly addressed.
Habit Support and Functional Retraining
Moving the teeth is only part of the picture. The muscles around the mouth need to support the new bite too, and any habits that keep the teeth apart need to be addressed.
For some children, this may involve practical habit support, orthodontic appliances that discourage thumb sucking or tongue pressure, and referral to an appropriate health professional if speech, swallowing or airway concerns need separate assessment.
When tongue posture, lip seal and swallowing patterns improve, the bite has a better chance of staying stable after treatment.
When Would Jaw Surgery Be Considered?
Most children with open bite concerns do not need surgery, especially when the issue is identified early. Surgical treatment is generally only considered for older teenagers or adults whose facial growth is complete.
If a patient has a severe skeletal discrepancy that cannot be corrected with orthodontic appliances alone, orthognathic jaw surgery may be discussed. This is carried out by an oral and maxillofacial surgeon working closely with the orthodontist.
For children, the priority is usually early monitoring, habit correction and growth guidance. The earlier we understand the pattern, the more options we usually have before adulthood.
Frequently Asked Questions
Can an open bite in a child correct itself naturally?
Yes, sometimes. If the open bite is linked to thumb sucking or dummy use, and the habit stops before the permanent front teeth come through, the bite may improve without active treatment. Skeletal open bites or persistent habits are less likely to self-correct and should be assessed by a specialist orthodontist.
What is the best age to seek an orthodontic assessment for an open bite?
I recommend a first orthodontic assessment by age seven. At this stage, the first adult molars and incisors have usually erupted, which makes it easier to check jaw growth, dental eruption and any habits that may be affecting the bite.
Can clear aligners be used to manage an open bite in children?
Yes, in selected cases. Clear aligners can help manage some open bites in growing patients, especially because the plastic over the biting surfaces can create a gentle bite-block effect. The right option depends on the cause of the open bite and the child’s growth stage.
How does tongue thrusting affect open bite treatment stability?
Tongue thrusting can make an open bite harder to correct and easier to relapse. If the tongue keeps pushing between the teeth during swallowing or at rest, it can continue to place pressure on the front teeth. That is why habit support and appropriate professional referral may be part of the treatment plan.
Is jaw surgery always necessary to correct a skeletal open bite?
No. Surgery is not always necessary, particularly when vertical growth issues are identified during childhood. Interceptive orthodontic treatment may help guide growth while the jaws are still developing. Surgery is usually reserved for severe skeletal discrepancies after facial growth is complete.
How do prolonged sucking habits contribute to an open bite?
Prolonged thumb sucking or dummy use can place steady pressure on the developing teeth and jaws. This may stop the front teeth from erupting fully and can narrow the upper jaw, creating a visible gap when the child bites down.
Helping Your Child Get the Right Open Bite Advice
At NK Orthodontist, we provide clear, honest and specialist guidance for families across Brisbane. Our practice has been helping local families manage children’s orthodontic development since 1995.
When you visit us, you can expect:
- Direct specialist care: I personally see every patient at every appointment. Your child’s care is never delegated to assistants or hygienists.
- Decades of experience: With over 30 years of specialist experience and more than 11,500 smiles treated, we understand how to work with your child’s natural growth.
- Convenient Brisbane care: We consult from Chermside, with appointment details confirmed when you book.
- Clear pricing: We offer transparent treatment plans with no hidden fees, along with interest-free payment options.
If you have noticed a gap between your child’s front teeth, or you simply want reassurance about their jaw development, we are here to help. Book an orthodontic consultation with Dr Nick to get clear advice for your child’s next step.
