Orthodontic assessment with digital scan
A 3D scan of both arches, photographs and, where needed, X-rays let us see the type and extent of the crossbite, check for a jaw shift and simulate how the teeth could move.
About this treatmentDental condition · Wimpole Street, Marylebone
Crossbite: when upper teeth close inside the lower ones
In a typical bite the upper teeth sit just outside the lower teeth all the way round the arch, like a lid slightly larger than its box. A crossbite is any place where that relationship flips and an upper tooth, or a run of them, closes inside its lower partner. It can involve a single front tooth that erupted behind the others, or the whole of one side at the back, often with the lower jaw swinging across to compensate. Many people live with a crossbite for decades without knowing. The reasons to correct one are practical rather than cosmetic: the affected teeth wear on the wrong surfaces, gums around them can recede, and chewing on one side loads the jaw joints unevenly. At Wimpole Street, assessment starts with a scan and a careful look at how you actually close, and correction, when advised, is usually possible with clear aligners.
Recognising it
How it usually feels
An upper front tooth sitting behind the lower teeth
Often a single lateral incisor that came through in the wrong place.
The chin or lower teeth appearing to shift to one side on closing
The jaw slides to find a comfortable position around the interfering teeth.
Upper back teeth biting inside the lower on one side
You may notice you chew mainly on the other side.
Flattened or chipped edges on particular teeth
Teeth meeting on surfaces not designed for it wear faster.
Gum receding on one or two specific teeth
Abnormal force angles and thin bone over a displaced tooth contribute.
Aching jaw muscles or clicking on one side
Asymmetric chewing over years can strain one joint more than the other.
Behind the symptoms
What's going on
- 01
A narrow upper jaw
When the palate is too narrow for the lower arch beneath it, the upper molars have nowhere to go but inside the lowers. This is largely inherited, though prolonged thumb sucking, dummy use and habitual mouth breathing in childhood can narrow the palate further.
- 02
Teeth erupting in the wrong position
When there is not enough room, an incoming tooth takes the path of least resistance, which for upper incisors and canines is often behind the arch. A baby tooth that hangs on too long can deflect its successor in the same way.
- 03
Jaw size mismatch
Some people inherit a lower jaw that is proportionally larger or further forward than the upper. Where the discrepancy is small it shows as a front crossbite of one or two teeth; where it is larger, the whole front segment may sit in reverse.
- 04
A functional shift
To get around a single interfering tooth, the lower jaw slides sideways or forwards every time you close. Over years this habit can become fixed, the muscles adapt, and in a growing child it may even influence how the jaw itself develops.
- 05
Tooth loss and drifting
In adults, losing a tooth allows neighbours to tilt and the opposing tooth to over-erupt. Occasionally this shifts a tooth into crossbite that was not there before.
- 06
Previous orthodontics without retention
Teeth expanded or moved during treatment tend to drift back if retainers are not worn. A corrected posterior crossbite is particularly prone to relapse without long-term retention.
Before your appointment
What you can do today
- Chew on both sides deliberately where you can, rather than always favouring the side that feels easier.
- Clean carefully around any tooth that sits out of line, since displaced teeth trap plaque and gum problems start there.
- If jaw muscles ache, a warm compress in the evening and avoiding very chewy food helps in the short term.
- Wear any retainer you were given after previous orthodontic treatment, even if it feels tight at first.
- In children, discourage thumb or dummy sucking beyond about age three, and mention persistent mouth breathing to your dentist or GP.
These are holding measures, not a substitute for an examination. Use any pain relief exactly as directed on the pack and check with a pharmacist if you take other medicines.
In the chair
How we treat it at Wimpole Street
Clear aligners
For single-tooth and mild-to-moderate crossbites in adults, a sequence of aligners moves the affected teeth across the bite. Small bite ramps or elastics are sometimes used to help teeth jump past each other.
About this treatmentFixed braces
Where several teeth are involved or rotation and expansion are needed, brackets and wires give more precise control. Ceramic brackets keep them discreet.
About this treatmentEarly treatment for children
In growing patients a palatal expander or simple appliance can widen a narrow upper jaw and remove a functional shift before the adult teeth are all through.
About this treatmentRetainers
Fixed or removable retainers hold the corrected position. For crossbites this is not optional; without retention the teeth drift back.
About this treatmentRepairing wear and recession
Once the bite is corrected, worn edges can be rebuilt with bonding and receding gums assessed for grafting if needed.
About this treatmentFees
Costs to expect
An orthodontic consultation at Wimpole Street, including the digital scan and a simulated outcome, is expected to be around £95 and is refunded against treatment if you proceed. Clear aligner treatment for a crossbite is indicative from £2,950 for a full course, with simpler single-tooth corrections at the lower end of the range.
Fixed braces are quoted after assessment and depend on complexity and duration. Retainers are included at the end of treatment, with replacements charged separately. Where bonding is needed afterwards to rebuild worn edges, it starts from £395 per tooth. All fees are set out in writing, and many patients spread the cost with interest-free instalments.
Figures are indicative prices for Wimpole Street and are confirmed in a written plan once a dentist has examined you. Fees match our South Kensington and St Paul's clinics.
Don't wait if
When to see a dentist
- You have noticed an upper tooth closing behind the lower teeth, or your jaw moving sideways as you bite.
- Particular teeth are wearing, chipping or becoming sensitive.
- Gum is receding around one or two teeth that sit out of line.
- You have pain, clicking or fatigue in one jaw joint.
- Your child has a crossbite or a habit such as thumb sucking past pre-school age.
- You are considering aligners and want to know whether the crossbite can be included.
FAQ
Common questions
No. A single-tooth crossbite that causes no wear, recession or jaw symptoms can reasonably be monitored. We recommend treatment when there is evidence of damage, a functional jaw shift, or when you would like the alignment improved. The decision is yours once you understand the risks either way.
Often, for mild to moderate cases in adults. Aligners can tip and expand upper molars to a degree, sometimes with the help of elastics. More significant skeletal narrowness may need fixed appliances or, rarely, a surgical approach, which we would explain at assessment.
Teeth can be moved at any age provided the gums and bone are healthy. What changes in adulthood is that the jaw itself no longer grows, so correction works within the existing skeletal frame. For most adult crossbites that is entirely sufficient.
A single displaced front tooth may take six to nine months with aligners. A posterior crossbite involving several teeth, or one combined with crowding, commonly takes twelve to twenty months. The scan-based simulation gives a realistic estimate for your case.
That is the functional shift. A tooth in crossbite gets in the way of the natural closing path, so the muscles steer the jaw around it. Removing the interference by moving the tooth usually allows the jaw to close straight again, often with relief of muscle tension.
The main long-term concerns are accelerated wear on the teeth meeting edge to edge, gum recession over displaced teeth, and uneven loading of the jaw joints. These develop slowly and not in everyone, which is why monitoring is a legitimate choice for mild cases.
Marylebone, W1
Wimpole Street opens 1 October 2026
Leave your details and we will be in touch when the Marylebone diary opens. If the problem cannot wait, the same clinicians are already seeing patients in South Kensington and at St Paul's.
Related conditions
Opening 1 October 2026
Wimpole Street is not yet seeing patients. Until then, please book or call our South Kensington clinic on 020 7183 2362 or our St Paul's clinic on 020 7183 3709. Questions about the new clinic: wimpolestreet@md.co.uk.
Until we open
Need an appointment before 1 October 2026?
The same clinical team already works from two other Medical & Dental clinics. Book at either one now and, if you prefer, move your ongoing care to Wimpole Street once the doors open.
South Kensington
- 20 Old Brompton Road, London SW7 3DL
- Open seven days a week
- 020 7183 2362
St Paul's, City of London
- 5 Ave Maria Lane, London EC4M 7AQ
- Open Monday to Friday
- 020 7183 3709
