Did My Child Get His Under Bite From Me?


Underbites, or mandibular prognathism, are characterized by the lower jaw protruding out past the upper jaw. This then causes the lower teeth to cover the upper teeth and can make people self-conscious.

But is an underbite hereditary?

“Most underbites are, in fact, hereditary,” says Dr. Nima Hajibaik, who provides underbites treatment in children. “Underbites affect between five and ten percent of the population, and for most people, it’s a trait they are born with.”

Some ethnic groups are actually more prone to developing underbites than the rest of the population. Those of Asian descent have a higher percentage of mandibular prognathism. The Habsburgs, a European royal family, were also known for their protruding jaws.

While you can’t fight your genes, there are some environmental factors that can lead to a protruding jaw, leading children to need underbites correction. They include:

  • Tongue thrusting – this occurs when the tongue is constantly pressed against the bottom teeth.
  • Mouth breathing, which can actually push the jaw forward while the jaw is being developed.
  • Poor lip and mouth posture

If you realize your child suffers from an underbite, early intervention is key to correcting it. The earlier you can catch it, the better the chances are that you’ll avoid more invasive treatment such as surgery in the future.

“Ideally, we would begin treatment for an underbite shortly after the child’s first orthodontic visit at the age of 7,” says Dr. Hajibaik. “This is because the jaw is still forming and we will better be able to reshape it.”

There are several procedures that can correct an underbite.

An upper jaw expander is used to widen the jaw. The expander is placed in the roof of the mouth and a key is turned each day to expand the jaw until the desired expansion has been reached and the width of the upper jaw matches the lower jaw. Once the proper expansion has been reached, the patient will wear a reverse pull headgear which is also called a face mask. This appliance is attached to the expander by rubber bands and It pulls the upper jaw forwards into a more proper location.

In cases of severe underbites, surgery may be required to adequately correct the jaw. While these treatments can help correct the jaw, braces will typically still be needed to correct the patient’s bite.

It’s crucial that treatment begin as early as possible. Once the jaw is fully formed, there are fewer treatment options and surgery is typically the only solution to correct the underbites. Again, braces will probably be used in addition to surgery to provide the most desirable result.

It’s important that you do not leave an underbite untreated. Malocclusions don’t just look unsightly, they affect how your mouth works, and how your jaws grow and can lead to a host of other dental problems in the future. Schedule a consultation with Dr. Nima today to learn how your underbites can be corrected.