A crossbite is a bite problem where some upper teeth sit inside the lower teeth when you close, instead of slightly outside them. It can affect front or back teeth and is usually corrected with an expander, braces or aligners, ideally during growth.
Crossbites are easy to miss at home, because the teeth can look fairly straight from the front even when the bite underneath is off. For families in Wichita, Goddard and Hutchinson, an exam at Hansen Orthodontics is the simplest way to find out. Here is what a crossbite looks like, why it matters, and how it is fixed.
What does a crossbite look like?
In a healthy bite, the upper teeth close just outside the lower teeth all the way around, like a lid on a box. With a crossbite, one or more upper teeth land behind or inside their lower partners. Sometimes it is a single tooth. Sometimes it is a whole side of the mouth.
To check at home, have your child bite down on their back teeth and smile wide. Look at the front: do any upper front teeth sit behind the lower ones? Then look at the sides: do the upper back teeth overlap the outside of the lowers, or do they tuck inside? Also watch whether the lower jaw slides to one side as the teeth come together. That shift is a common clue.
A home check is only a first look. Some crossbites are subtle, and an orthodontic exam with digital scans and X-rays gives the full picture.
What are the different types of crossbite?
Orthodontists group crossbites by where they happen. An anterior crossbite involves front teeth, where one or more upper front teeth sit behind the lower front teeth. It can look similar to an underbite, but an underbite usually involves the whole jaw relationship, while an anterior crossbite may involve only a tooth or two.
A posterior crossbite involves the back teeth. It can be unilateral, on one side only, or bilateral, on both sides. Posterior crossbites are often linked to an upper jaw that is narrower than the lower jaw, which is why widening the upper jaw is a common part of treatment.
Crossbites are also described by cause. A dental crossbite comes from a tooth erupting in the wrong position. A skeletal crossbite comes from the size or shape of the jaws themselves. The cause shapes the treatment, so it is one of the first things an orthodontist works out.
What causes a crossbite?
Many crossbites come down to how the jaws grow. If the upper jaw is narrow, the upper teeth have less room to sit outside the lowers. Genetics plays a role, so it is common to see similar bites in parents and children.
Habits can contribute too. Prolonged thumb sucking or pacifier use can narrow the upper arch over time, and breathing mostly through the mouth can affect how the palate develops. Baby teeth that are lost too early or too late can also steer adult teeth into the wrong spot. You will notice some of these on our list of signs your child may need braces.
Why should a crossbite be treated?
A crossbite is more than a cosmetic concern. When the lower jaw has to shift sideways to close, the jaw joint and chewing muscles work at an angle every time your child eats. Over years, that can contribute to uneven wear on the teeth, strain on the jaw, and sometimes jaw discomfort. If jaw pain or clicking is already part of the picture, our TMJ treatment page explains how we approach it.
Teeth in crossbite can also rub against each other in ways they were not designed to, which may wear enamel or stress the gums around them. And when the jaw shifts to one side during growth, it can grow unevenly, which is harder to correct later.
Not every crossbite needs immediate treatment, but every crossbite deserves a look. That is part of why the American Association of Orthodontists recommends a first orthodontic evaluation by age seven, a topic we cover in why age 7 matters.
How is a crossbite corrected?
Treatment depends on the type of crossbite, its cause and the patient’s age. In growing children with a narrow upper jaw, a palatal expander is often the first step. The expander sits against the roof of the mouth and gradually widens the upper jaw, creating room for the upper teeth to sit in their proper place. Our other treatments page notes that an expander can also help with breathing, which is part of our approach to airway orthodontics.
When the problem is mainly the position of the teeth, braces or clear aligners can move individual teeth into the right spot. Invisalign Teen can treat crossbites in many cases, and braces can be paired with appliances when more control is needed. Small anchors called TADs are sometimes used to give a fixed point for precise tooth movement.
For adults whose jaws have finished growing, a skeletal crossbite may need a combination of orthodontics and jaw surgery with an oral surgeon. Surgery is only considered when braces alone cannot correct the problem, and many adult crossbites can be improved without it.
How do crossbite treatments compare?
This overview shows how the main options line up. Your plan may combine more than one.
| Treatment | What it does | Usually used for | Timing |
|---|---|---|---|
| Palatal expander | Gradually widens the upper jaw | Posterior crossbite with a narrow upper jaw | Most effective while the jaw is still growing |
| Braces | Moves individual teeth into position | Dental crossbites and finishing after expansion | Children, teens and adults |
| Clear aligners | Moves teeth with a series of custom trays | Many dental crossbites in children, teens and adults | From childhood (Invisalign First) through adulthood |
| Jaw surgery with orthodontics | Repositions the jaw bones | Severe skeletal crossbites | Only after jaw growth is complete |
Is it better to treat a crossbite early?
Often, yes. Children’s jaws are still growing, and the seams in the upper jaw respond well to expansion at a young age. Correcting a crossbite while growth is on your side can be simpler than correcting it later, and it can help the jaw grow evenly instead of shifting to one side.
That is why crossbites are a common reason for early, or Phase One, treatment. After a first phase, there is usually a resting period while adult teeth erupt, followed by a second phase to fine-tune alignment. Our post on two-phase orthodontic treatment explains how the two stages fit together. Early treatment is not right for every child, and an exam shows whether watching and waiting makes more sense.
Frequently Asked Questions
Can a crossbite fix itself?
A crossbite caused by jaw width usually does not correct itself as a child grows, and a jaw that shifts to close can grow unevenly. An exam is the surest way to know whether to treat now or monitor.
Can adults fix a crossbite without surgery?
Many can. If the crossbite comes mostly from tooth position, braces or clear aligners can often correct it. Severe skeletal crossbites in adults may need jaw surgery along with orthodontics.
Does a palatal expander hurt?
Most kids feel pressure in the teeth, roof of the mouth or nose for a few days as the expander is adjusted. It is usually mild and fades as they get used to it.
Is a crossbite the same as an underbite?
Not exactly. An underbite usually means the whole lower jaw sits forward of the upper jaw. A crossbite can involve just one tooth or one side of the mouth.
Get Your Child’s Bite Checked in Wichita
If you have noticed teeth tucking inside, a jaw that slides to one side, or trouble chewing, a quick exam can answer your questions. Dr. Hansen sees patients in Wichita, Goddard and Hutchinson. Call or text (316) 722-6717 or request a free consultation today.