Aligners for crossbite

A crossbite is when some upper teeth sit inside the lower teeth when you bite together, instead of just outside them. Normally the upper teeth close slightly outside the lower teeth all the way round. In a crossbite, one or more teeth are on the wrong side.

A crossbite can affect a single tooth, a group of front teeth or the back teeth on one or both sides. When all the lower front teeth sit in front of the upper ones, it is usually called an underbite.

Crossbites are easy to miss, because they rarely hurt. Many people only find out they have one at a dental check.

A crossbite should be treated because it can wear and chip the teeth involved, push the lower teeth and gum out of position, and make the lower jaw shift to one side when you close. In children, a crossbite left alone can affect how the jaws grow.

When a front tooth is in crossbite, the lower tooth it bites against is pushed forward with every bite, which can thin the gum on its front surface over time. Back crossbites can make the jaw slide sideways to fit the teeth together.

Some mild crossbites cause no problems and may not need treatment. The examination tells you whether yours is likely to cause wear, gum or jaw problems, and whether treating it is worthwhile.

Sometimes. Aligners can correct a mild back crossbite where the upper back teeth are tipped slightly inward, by tipping them outward a little with each tray. A back crossbite caused by a narrow upper jaw usually needs the jaw itself widened, which aligners cannot do.

In children, a narrow upper jaw is often widened with a palatal expander while the jaw is still growing, which is the most effective time to correct it. In adults, the jaw has stopped growing, so a skeletal back crossbite may need surgically assisted expansion for a full correction.

Many adults choose an improvement rather than a full correction, accepting a small crossbite that causes no problems. The clinician explains what each option would achieve.

Aligners correct a dental crossbite by moving the teeth involved to the correct side of the bite: tipping back teeth outward, or moving a front tooth forward over the lower teeth, a small planned step with each tray. Both arches are usually planned together.

Moving a tooth past the opposite teeth needs the plan to account for the bite at every stage. Attachments may be added for grip, and some plans use small elastics between the trays. Your plan shows exactly what your case needs, and our guide to how teeth aligners work explains each part of treatment.

Where crowding caused the crossbite, space is made first, so the tooth has somewhere to go.

In children, a crossbite is often treated early, while the jaws are still growing, because a narrow upper jaw is easiest to widen at that stage and a jaw that shifts sideways can grow unevenly. Treatment is usually with an expander or other appliance under an orthodontist.

NHS guidance on orthodontics makes the same point, that treatment is planned around an assessment of how the teeth and jaws fit (NHS on orthodontics). For parents, the practical step is a check at around seven or eight, when the first adult incisors are in.

Teenagers whose crossbite is dental, rather than a narrow jaw, are usually good aligner candidates.

A front crossbite can damage the gum. When an upper tooth bites behind a lower tooth, it pushes the lower tooth forward with every bite, which can thin the gum and bone on the front of that lower tooth and lead to recession.

This is one reason a single tooth crossbite is worth correcting even when it does not bother you cosmetically. Correcting it removes the force on the lower tooth.

If the gum is already receding, the clinician will check it before treatment and may advise a gum assessment.

A crossbite does not usually correct itself, and the damage it causes, such as wear, chipping and gum thinning on the lower teeth, tends to build up over the years. In children, a crossbite with a jaw shift can become harder to correct as growth continues.

That is why crossbites are often treated earlier than purely cosmetic crowding. Even a mild crossbite is worth having checked so you know whether it is likely to cause problems.

At a crossbite assessment, a clinician checks which teeth are in crossbite, how the jaws relate, whether the jaw shifts when you close, and the health of the gums around the teeth involved. An x-ray may be advised.

Expect questions about thumb sucking or mouth breathing as a child, clicking or aching in the jaw, and what you dislike about your bite. You leave knowing which of three paths fits: aligners alone, aligners with an improvement rather than a full correction, or an expander, braces or surgery.

When aligners are the right path, a scan is taken that day and your plan and price follow in writing.

A scissor bite is the opposite of a back crossbite: an upper back tooth sits completely outside the lower tooth, so the two slide past each other like scissor blades instead of meeting. It is less common than a crossbite and usually affects one or two premolars or molars.

Because the teeth do not meet at all, a scissor bite can make chewing on that side less effective and can let the teeth over erupt. Aligners can often bring a single tooth in scissor bite back into contact by tipping it inward.

Like a crossbite, a scissor bite is assessed in person first, because the cause can be the tooth, the width of the arch or both.

Mouth breathing in childhood is linked to a narrower upper jaw, which is a common cause of back crossbites. When the mouth stays open, the tongue rests low instead of against the roof of the mouth, and the upper arch can develop narrower as a result.

This is one reason children with a back crossbite are often asked about snoring, blocked noses and allergies. Treating the breathing problem, as well as widening the jaw while the child is growing, gives the best long term result.

In adults, the jaw has finished growing, so the crossbite is treated directly, but the history still helps explain why it developed.

Sometimes. A single upper tooth caught behind the lower teeth can occasionally be corrected by moving only the upper arch. Most crossbites, though, are planned with both arches, because the correction depends on how the upper and lower teeth meet.

Treating both arches lets the plan move each tooth the shortest safe distance, often moving a lower tooth slightly back while the upper tooth comes forward. The clinician explains which approach your case needs.

No. A crossbite cannot be safely corrected at home, and a retainer holds teeth in place rather than moving them across the bite. Trays bought online without an examination cannot tell whether the cause is the teeth or the jaw.

Pushing a tooth across the bite without a plan can damage the gum and bone around it, especially on the lower tooth it bites against. A crossbite needs a clinically planned appliance and regular checks.

Yes. A crossbite on one side is often caused by the jaw sliding sideways to find a comfortable bite, while a crossbite on both sides usually means the whole upper arch is narrow. The first can sometimes be corrected by adjusting a few teeth; the second usually needs the arch itself widened.

The sliding jaw is the key sign. If, when you close slowly, your teeth first touch in the middle and then the jaw slips to one side, the crossbite may be functional rather than structural, which often makes it easier to treat.

The clinician checks this by guiding your jaw gently as you close, which takes only a moment at the examination.

A front tooth in crossbite chips easily because its thin edge takes the force of biting against the lower teeth at an angle it was never shaped for. Over time, both that tooth and the lower tooth it hits can wear, chip or develop small cracks along the edge.

Once the tooth sits in front of the lower teeth, it meets them the way it should, and the chipping stops. Any edges already worn can be repaired with bonding after the bite is corrected, if you want them to look even. Doing it in that order matters, because bonding placed while the tooth is still in crossbite would chip just as the enamel did.

Braces or expanders are better than aligners when the upper jaw is too narrow, when the crossbite is skeletal, or when large movements need the constant control of a wire. Growing children with a narrow upper jaw usually do best with an expander first.

Where the crossbite is dental, trays usually win on comfort and discretion, and our comparison of aligners vs braces sets out the trade offs in full.

With aligners for crossbite, you can expect the teeth involved to move to the correct side of the bite, as shown in your digital plan, when the crossbite is dental and the trays are worn as prescribed. When jaw width is part of the problem, expect a better bite rather than a perfect one, and you will hear that before you agree to anything.

Retention is part of the result. A corrected crossbite needs retainers to hold the teeth on the correct side while the bone settles.

A corrected crossbite can relapse if retainers are not worn, particularly a back crossbite that was corrected by tipping teeth outward. Wearing retainers as advised keeps the teeth on the correct side of the bite.

Plan on regular retainer wear for around half a year once the trays finish, then retainers at night from then on. A front tooth that now clears the lower teeth is often helped to stay put by the bite itself.

Teeth Aligners offers aligners for crossbite in Islamabad, Rawalpindi, Lahore, Sargodha and Gilgit, always after the bite has been examined in person, and our own laboratory in Pakistan makes every tray.

If you live abroad, plan your first crossbite appointment around a trip home; photos show alignment well but not how the jaws close. Later checks can usually be done by photo.

You can meet the clinicians who treat aligner patients on our doctors page.