Top 10 Signs a Child May Need an Orthodontic Assessment

How we ranked these signs

These signs are ordered by how easy they are for a parent to see without any equipment, starting with what shows in a photograph and finishing with signs that are about function, breathing or injury. That is an editorial judgement based on NHS and professional guidance, not a survey, and it does not claim to show which sign is most common or which matters most clinically. Several signs often appear together, and a child can have a perfectly normal bite and still show one of them for a while. The list is meant to help you decide what to mention at a dental check-up, not to diagnose your child. Only a dentist or orthodontist who examines your child can say whether anything needs to happen and when.

Why noticing early helps, and what it does not mean

Most children who need orthodontic treatment have it in their early teens, once most of the adult teeth have come through, and the NHS describes treatment as usually being carried out during these years. That does not mean there is nothing to look out for before then. Some problems, such as a crossbite or a tooth that is blocking another from coming through, can sometimes be dealt with more simply when they are found early, and others are best watched and reviewed at intervals. Seeing a sign does not mean your child will need braces, and it does not mean treatment is urgent. Your dentist looks at your child's teeth at every check-up, so the aim is to give them a clear picture of what you have seen. In England, NHS orthodontic treatment for under-18s depends on clinical need, which is measured with the Index of Orthodontic Treatment Need.

1. Crowded or overlapping teeth

Crowding means there is not enough room in the jaw for all the teeth, so they twist, overlap or push out of line. Parents often first notice it when the lower front adult teeth come through at the age of about six or seven and sit slightly crooked, which is common and can improve a little as the jaw grows and baby teeth are replaced. Mild crowding is often only a cosmetic concern, while severe crowding can make cleaning harder, leave plaque trapped between overlapping teeth and sometimes stop later teeth from finding a place. A dentist can tell you whether the crowding is likely to settle or whether to monitor it, and an orthodontist can explain the options as the adult teeth arrive. Early removal of baby teeth is sometimes discussed but is a clinical decision. Watch out for deciding at home that crowding will sort itself out, because the pattern becomes clearer as more adult teeth erupt and a check costs little.

2. Upper front teeth that stick out

When the top front teeth sit well forward of the bottom teeth, the bite is often described as having an increased overjet. It may be caused by the position of the teeth, the relationship between the upper and lower jaws, or a long-running thumb or dummy habit. Beyond how it looks, prominent upper front teeth are more likely to be damaged in a fall or a sports accident, which is one of the reasons the British Orthodontic Society and dentists take them seriously. Some children are teased, and the effect on confidence is a genuine factor that clinicians consider alongside the clinical findings. Timing depends on the cause. Where a habit is involved, stopping it matters first, and where the jaw relationship is the cause, the orthodontist may choose to wait for growth. A mouthguard for contact sports is sensible whatever the plan. Watch out for assuming a forward tooth position is just a family trait that needs no comment, since it is worth mentioning at a check-up.

3. Crossbite or a jaw that shifts when the mouth closes

In a crossbite, some of the upper teeth bite inside the lower teeth instead of outside them. It can affect a single front tooth or the back teeth on one or both sides. A particular reason to look at it is a jaw that slides to one side as your child closes, because the teeth then meet in a position that is not where the jaw naturally rests. You might notice a lower jaw that seems off-centre in photographs, or a chin that points slightly to one side. A dentist or orthodontist can check whether the crossbite involves a shift and whether it is worth correcting while the child is still growing, as some can be treated with a simple appliance. Others are monitored, and treatment is never automatic. Watch out for waiting years on a shifting bite, since a review lets the clinician pick the right moment rather than guessing.

4. Lower teeth that bite in front of the upper teeth

An underbite, sometimes called a Class III bite, is when the lower front teeth sit in front of the upper front teeth when the child bites together. It can come from the position of the teeth, from the way the jaws have grown or from a combination of the two. Because the jaws are still growing in childhood, the pattern may change over time, which is why an orthodontist often wants to follow the bite rather than act at once. In some children a short period of early treatment is suggested, while in others the decision is to wait until growth is nearly complete, and in a small number of cases jaw surgery may later be discussed. A family history of a prominent lower jaw is worth mentioning to the clinician. Watch out for assuming a lower jaw that seems prominent will straighten without a review, as the right timing depends on the type of bite.

5. A deep bite where the top teeth hide the bottom teeth

In a deep bite, the upper front teeth cover much more of the lower front teeth than usual when the child bites together. In some children the lower teeth bite into the gum behind the top teeth, which can be uncomfortable or cause damage over time. A deep bite can also wear the edges of the teeth faster and can sometimes accompany a narrow arch or a jaw relationship that an orthodontist may want to follow. Parents may notice that the lower teeth almost disappear when their child smiles with the teeth together, or that the child complains about the roof of the mouth. Many mild deep bites are harmless and are simply watched, and the NHS and the British Orthodontic Society emphasise that treatment depends on the individual child. Where treatment is advised, timing is linked to growth and tooth eruption. Watch out for dismissing pain or soreness behind the upper teeth, which should be checked.

6. An open bite and thumb or dummy habits

An open bite means that some teeth do not meet when the child bites down, most often leaving a gap at the front through which you can see the tongue. Thumb or finger sucking, a dummy used well beyond the toddler years and a tongue that pushes forward when swallowing are all linked with it, although genes and jaw shape can also play a part. The NHS advises that prolonged dummy and thumb habits can affect how the teeth come through, and the usual advice is to encourage the child to stop gently, with praise, rather than with punishment. Many open bites improve once a habit stops, particularly in younger children, while others need an orthodontist's input. Speech, such as a lisp, may sometimes be noticed alongside it, although orthodontics is not a speech treatment. Watch out for nagging or shaming a child about a comfort habit, which can make it harder to break.

7. Baby teeth lost very early or very late

Children lose their baby teeth in a broad pattern, but the timing varies, and what matters is how far a child is from that pattern. A baby tooth lost very early, for example through decay or an injury, can allow neighbouring teeth to drift into the space and make it harder for the adult tooth to come through, which is why dentists sometimes talk about a space maintainer. A baby tooth that is still firmly in place long after its adult replacement has appeared, sometimes causing a double row of teeth, or one that simply does not wobble when its pair on the other side has gone, is also worth a look. Late shedding may be nothing, and sometimes it signals that the adult tooth is missing or is coming through in the wrong place. A dentist can usually tell from the mouth alone and may recommend an X-ray. Watch out for pulling a stubborn tooth at home, because it can leave the adult tooth worse off.

8. Missing or extra teeth

Some children are born without one or more adult teeth, which is called hypodontia, and some have an extra tooth, called a supernumerary tooth. The signs for parents are a gap that does not close after a baby tooth has fallen out, an unusually long wait for the replacement to appear when the same tooth on the other side has already come through, or a front tooth that is out of line with an additional small tooth behind or between others. Both situations can change how the other teeth line up, and the planning may involve the dentist, an orthodontist and sometimes a restorative specialist. Which teeth are missing, and how much space is left, affects whether the gap is closed, held open or filled later on. An X-ray is the standard way to confirm what is present under the gum, and the dentist will decide whether it is needed. Watch out for assuming a late tooth is just slow, because a simple check can settle it.

9. Adult teeth coming through in the wrong place

Adult teeth normally emerge in a predictable order, and the upper canines, often called eye teeth, tend to come through towards the end of the process in the early teens. If one is visibly high in the gum, sitting forward of the line of the teeth, or is not felt in the gum where its partner on the other side can be, dentists may want to look more closely. Guidance used by dentists in the UK recommends considering a closer look, which can include an X-ray, when a canine is not where it is expected at about this stage of development, although the details are a clinical decision. Sometimes the baby canine is removed to help the adult tooth find its way. An impacted tooth that is found late can need a longer and more involved treatment. Watch out for leaving a possible canine problem until the late teens, since an earlier check gives the clinician more options.

10. Trouble chewing, mouth breathing or an injury to the teeth

Some signs are about how the mouth works rather than how it looks. A child who finds it hard to bite into an apple, chews on one side only, has a jaw that clicks or aches, or breathes through the mouth with the lips apart at rest is worth mentioning to a dentist, and sometimes to a GP as well. Mouth breathing can have many causes, including blocked noses and enlarged tonsils, and a dentist cannot treat those, although they may influence how a child's face and teeth develop and are worth getting looked at. A knock to a front tooth, even one that seems fine, should be checked, because teeth can change colour or loosen later. Ask for a referral where something affects eating, sleeping or comfort. Watch out for waiting to see if mouth breathing disappears without an explanation, since an underlying cause may need its own treatment.

What usually happens at an orthodontic assessment

An assessment is mostly a conversation and a careful look. The clinician asks about your child's health, habits and any history of injury, looks at the teeth and how they meet, checks the jaw and may take photographs, scans or impressions. An X-ray is used only when it will change the plan, for example to see which teeth are present under the gum. The result is usually one of three things: no treatment is needed, your child is reviewed at intervals as the adult teeth arrive, or treatment is proposed now or later with an explanation of the type of appliance, how long it is likely to take and what it involves. For NHS care, the clinician will also assess need using the Index of Orthodontic Treatment Need. You are entitled to ask questions, to take time to decide and to ask for the plan in writing. Children should be involved in the conversation.

What you can look at at home before the appointment

You do not need special equipment to prepare. Look at your child's smile in good light with the teeth gently together, and note whether the middle of the top and bottom teeth line up, whether any top teeth sit inside the bottom ones and whether there is a gap at the front. Ask your child to open and close slowly while you watch for a slide to one side, and check whether the tongue shows between the teeth when they swallow. Write down when baby teeth were lost and which adult teeth have come through, any thumb, finger or dummy habits and any knocks to the teeth. Take clear photographs from the front and each side, because they are useful to compare later. Do not try to move teeth at home or buy a product online, and do not use anything that is not fitted by a registered professional.

NHS or private: what to expect

In England, Scotland, Wales and Northern Ireland, the usual route to an NHS orthodontist is a referral from your child's general dentist. NHS orthodontic treatment for under-18s is available when the clinical need meets the national threshold, and it is free of charge for the child. Waiting times vary by area and can be long, so it helps to ask your dentist about the local picture. Seeing an orthodontist privately is an alternative, and a private assessment does not by itself take away your child's NHS entitlement, although it is sensible to ask the practice how it works. Check that the person treating your child is on the General Dental Council register as an orthodontist or dentist, and ask what the total cost covers, including retainers. Costs for private treatment vary a lot between practices and cases, so ask for a written estimate.

When to seek help sooner

Most of the signs above can wait for a routine appointment. Some things should not. A knocked or broken tooth, a swelling in the gum or face, a toothache that keeps your child awake or a tooth that has become loose after a blow need a dentist promptly, and the NHS advises using 111 for urgent dental problems if you cannot reach your own dentist. A child with trouble breathing needs medical help rather than an orthodontic appointment. If your child wears a brace already and something has broken, contact the practice that fitted it. If you are worried and are not sure how serious it is, ring your dentist and describe what you see, because they can often tell you quickly whether it can wait or needs to be looked at now.

Key takeaways

Most children do not need braces, but ten signs are worth raising with a dentist: crowding, teeth that stick out, a crossbite or jaw shift, an underbite, a deep bite, an open bite or long-running habit, baby teeth lost much too early or late, missing or extra teeth, adult teeth in the wrong place, and trouble chewing, breathing or injury. Seeing one does not mean treatment, and many problems are simply watched. Note what you see, take photographs and mention it at the next check-up, since NHS referrals start with your dentist. Never try to move teeth at home. This is general information, not personal medical advice, and your child's dentist and orthodontist should guide any decision.

Useful related pages

This guide is for general information only. It is not a diagnosis, treatment plan, or substitute for advice from a registered dentist or orthodontist.