A crossbite occurs when some of the upper teeth are situated behind the corresponding lower teeth when the jaws are closed. This can happen on one or both sides of the mouth and can involve the front or back teeth. Crossbites can cause a variety of problems, including dental problems, jaw pain, asymmetries, and gum recession.
There are two types of crossbites: anterior and posterior. An anterior crossbite (also sometimes called an underbite) is when the front teeth are misaligned, causing the upper teeth to sit inside the lower teeth. A posterior crossbite is when the upper teeth to sit inside or outside the lower teeth. Posterior crossbites are more common than anterior crossbites and are often caused by a narrow upper jaw.
What causes crossbites?
There are several causes of crossbites. Some people are born with crossbites, while others develop them as a result of habits such as finger or thumb sucking. Crossbites can also be caused by a narrow upper jaw, missing teeth, or crowded teeth. In some cases, crossbites can be a result of a skeletal issue with the jaw itself.
What happens if you don’t correct a crossbite?
Left untreated, crossbites can lead to a variety of dental problems, including:
Uneven tooth wear. Crossbites can cause certain teeth to wear down faster than others due to the constant pressure and friction.
Gum recession. This is more of a concern with anterior crossbites involving the front teeth. As the lower teeth get pushed forward, they are moved towards the edge of the jaw bone and the gum can become very thin and can recede, making the tooth look longer than it should be.
Pain. There are some reports that crossbites can cause pain in the jaw or cause headaches due to the uneven pressure on the teeth and jaws. This is not always the case though and sometimes jaw pain and headaches may persist even after the crossbite has been corrected with braces.
Speech difficulties. Crossbites can affect speech, particularly the pronunciation of certain sounds.
Self-esteem issues. Misaligned teeth can also affect a person’s self-esteem and confidence, particularly if the crossbite is visible when smiling or speaking.
What can be done to correct crossbites?
Fortunately, crossbites can be corrected with orthodontic treatment. Depending on the severity of the crossbite, the treatment may involve braces, a palatal expander, or a combination of both.
For an anterior crossbite in a child, correction can be achieved with an upper removable appliance. If worn well, these braces are extremely effective and the crossbite can be resolved in as little as 3-6 months.
An upper removable brace can also be used as an expander to correct posterior crossibtes and works by widening the upper jaw to create more space for the teeth. For more severe posterior crossbites in children, rapid palatal expansion may be a better option.
In some cases, a crossbite may require surgery to correct. This is typically reserved for cases where the crossbite is severe or is caused by a skeletal issue with the jaw. Surgery may involve repositioning the jaw or reshaping the bone to correct the alignment of the teeth.
In addition to orthodontic treatment, there are a few things that people can do to prevent crossbites. For example, parents can discourage their children from thumb sucking, which can cause many issues, including posterior crossbites. Regular dental check-ups can also help detect crossbites early on when they are easier to correct.
At what age should crossbites be corrected?
Anterior crossbites involving the front teeth should be treated as early as possible, soon after the permanent incisors erupt. An untreated anterior crossbite and lead to gum recession and tooth wear.
Posterior crossbites can be treated early, in pre-adolescent children, using expanders. The benefits of early treatment are unclear, an it is often better to wait and combine expansion with any other orthodontic treatment that needs to be done. Doing it like this will generally reduce costs and will shorten the overall treatment time.
There are fewer treatment options for adults with crossbites and correction can become more difficult.