When most people say “open bite,” they’re referring to an anterior open bite. People who have an anterior open bite have front upper and lower teeth that slant outward so they don’t touch when the mouth is shut.

An open bite is a type of malocclusion, which means the teeth aren’t aligned properly when the jaws are closed.

Open bite is primarily caused by four factors:

  1. Thumb or pacifier sucking. When someone sucks on their thumb or a pacifier (or another foreign object like a pencil), they strain the alignment of their teeth. This can cause an open bite.
  2. Tongue thrusting. An open bite can occur when a person speaks or swallows and pushes their tongue between their upper and lower front teeth. This can also create gaps between teeth.
  3. Temporomandibular joint disorder (TMD or TMJ). TMJ disorders cause chronic jaw pain. Sometimes people use their tongue to push their teeth apart and comfortably reposition their jaw, which can cause an open bite.
  4. Skeletal problem. This occurs when your jaws grow apart as opposed to growing parallel to each other and is often influenced by genetics.

Many treatments are available. A dentist will make specific recommendations based on the person’s age and whether they have adult or baby teeth. Treatment methods include:

  • behavior modification
  • mechanical treatment, such as braces or Invisalign
  • surgery

When open bite occurs in children who still have most of their baby teeth, it can resolve on its own as the childhood action causing it —thumb or pacifier sucking, for example — stops.

If the open bite occurs as the adult teeth are replacing the baby teeth, but aren’t fully grown in, behavior modification might be the best course of action. This may involve therapy to correct tongue thrusting.

If the adult teeth are growing into the same open bite pattern as the baby teeth, an orthodontist may recommend getting custom braces to pull the teeth back.

For people with adult teeth fully grown in, a combination of braces and behavior modification is often suggested. In severe cases, jaw surgery to reposition the upper jaw with plates and screws may be recommended.

Other treatments include the use of a roller appliance to limit the ability of the tongue to thrust against the front teeth and the use of headgear that applies force to pressure the jaws into position for properly aligned growth.

The side effects of an open bite range from aesthetic concerns to fractured teeth:

  • Aesthetics. A person with an open bite may be unhappy with the appearance of their teeth because they look like they’re sticking out.
  • Speech. An open bite can interfere with speech and pronunciation. For example, many people with open bite develop a lisp.
  • Eating. An open bite can prevent you from properly biting and chewing food.
  • Tooth wear. As the back teeth are coming together more often, the wear can lead to discomfort and other dental problems including fractured teeth.

If you experience any of these side effects from an open bite, make an appointment with a dentist or an orthodontist to talk about treatment options.

An open bite is treatable at any age, but it’s much easier and less painful to treat when adult teeth aren’t fully grown in.

Children with an open bite should have a dental evaluation while they retain some baby teeth, at about 7 years old. This is a good age to start certain procedures — including behavior modification — to avoid open bite as these children grow.

For adults, addressing an open bite is more complicated. It might require a combination of behavioral and mechanical treatment (such as braces), or even need jaw surgery.