Crossbite: types and treatment

Page updated October 14, 2026. Medically reviewed by Dr. Abraham Thomas and Dr. Jennifer Loucks-Buren.

A crossbite is when some upper teeth sit inside the lower teeth when you bite down, at the back of the mouth, the front, or both. It's usually fixed with a palatal expander in growing children and with braces or aligners at any age; severe adult cases may need jaw surgery. Treatment typically takes 18 months to 3 years.

What a crossbite is

A crossbite is a common form of malocclusion, or misaligned bite, in which the upper teeth sit inside the lower teeth, or upper back teeth bite completely outside the lower ones (AAO). It can affect one tooth, several, or groups of teeth, at the front or back of the mouth (AAO). Cleveland Clinic's definition is simply that your upper teeth fit inside your lower teeth when you close your mouth (Cleveland Clinic).

A crossbite isn't the same as an underbite. Healthline explains the difference as scope: a crossbite affects a group of teeth, an underbite all of them (Healthline). The AAO notes that when all the upper front teeth or the whole jaw sit behind the lower front teeth, the term underbite is often used (AAO).

Types of crossbite

A crossbite can be on one side or both, and can involve a single tooth or a whole section of the arch (AAO).

Signs of a crossbite

The main sign is upper teeth fitting inside the lower teeth, at the back or front, when you bite down normally; if you suspect one, see an orthodontist (AAO). Healthline lists symptoms adults may notice with an ongoing crossbite (Healthline):

• Pain in the jaw or teeth, or in the jaw, neck and shoulder muscles
• Tooth decay
• Temporomandibular joint (TMJ) disorders and frequent headaches
• Difficulty speaking or forming certain sounds
• Sleep apnea

In children, the AAO's warning signs include jaws that shift or click and frequent cheek biting (AAO).

What causes a crossbite

Causes can be dental (the teeth) or skeletal (the jaws), and both can be inherited (Healthline). The AAO lists (AAO):

• Genetics
• Baby teeth that are lost late
• Adult teeth that come in abnormally
• Long-lasting habits such as thumb sucking or atypical swallowing

Healthline adds mouth breathing late into childhood (Healthline). These habits put pressure on the teeth that can push them out of place and distort the bone (AAO).

How a crossbite is diagnosed

A dentist can spot a bite problem at a regular check-up, often using impressions, X-rays and photos of how the teeth fit together, and may refer you to an orthodontist, a specialist in aligning the bite (Cleveland Clinic). You can also book an orthodontist directly; you don't need to wait for a referral (AAO). The orthodontist decides whether the crossbite comes from the teeth, the jaws or both, which shapes the treatment (Healthline).

Crossbite vs other bite problems

Why it's worth treating

A crossbite isn't only cosmetic. Left untreated, it can make the jaw shift to one side, cause lopsided jaw growth and wear down tooth enamel (AAO), and can lead to gum disease and jaw problems (AAO). Misaligned teeth are harder to clean, which raises the risk of decay and gum disease (Healthline). In severe untreated cases, jaw surgery may eventually be needed (AAO). Bite problems in children usually don't fix themselves and often get worse (AAO).

Crossbite treatment in children

Childhood is the best time, because the face and jaws are still developing (AAO). For growing patients, a common approach is a palatal expander to widen the upper jaw, followed by braces or clear aligners to position the teeth (AAO). The AAO's expander guide lists crossbite among the most common problems expanders treat, by widening the underlying bone (AAO). Healthline says treatment can begin before age 10, and that braces or headgear may also be used (Healthline).

That's why the AAO recommends an orthodontic check by age 7, often at no cost (AAO). More in braces for kids and teens.

Crossbite treatment in adults

Adults with milder crossbites can use orthodontic treatment such as braces, removable palate expanders, elastics and retainers (Healthline); see rubber bands for braces. With the jaws fully grown, a more severe skeletal crossbite may need jaw surgery to reset the jaw, with braces to finish the correction (Healthline). Read about jaw surgery cost and recovery and adult braces.

How long it takes: anywhere from 18 months to 3 years, depending on severity (Healthline).

Can Invisalign fix a crossbite?

Sometimes. The AAO lists braces or clear aligners for moving the teeth once the jaw has been widened in growing patients (AAO). But aligners may not work as predictably for severe malocclusions (AAO), and a skeletal crossbite in an adult may need surgery (Healthline). Your orthodontist decides; compare prices on Invisalign vs braces.

After treatment

Once the bite is corrected, a retainer holds it, as with any orthodontic treatment: full time for a few months, then at night indefinitely (AAO). A corrected crossbite also makes teeth easier to clean, lowering the risk of decay and gum disease (Healthline).

Questions to ask your orthodontist

• Which type of crossbite is it, and is it from the teeth, the jaws or both?
• Will my child need an expander first, and for how long (AAO)?
• Will I need surgery, and if so, before, during or after braces (Cleveland Clinic)?
• How long will treatment take (Cleveland Clinic)?
• Would insurance treat it as medically necessary (Healthline)?

How much crossbite treatment costs

Insurance may help. Medical insurance may cover some treatment if the crossbite is medically necessary, dental plans with orthodontic benefits may cover children, and adult coverage is rare but worth checking (Healthline). See dental insurance for braces and the cost calculator.