What Is an Underbite and What Are the Treatment Options?

An underbite occurs when the lower teeth sit further forward than the upper teeth. This condition is often genetic, and underbite correction with orthodontics is usually recommended to avoid problems later in life.

It is possible to fix an underbite; surgery and braces are common options, along with some other treatments. Here, we’ll talk you through everything that you need to know about this type of dental malocclusion and how it may affect you or your child.

What is an underbite?

An underbite occurs when the lower jaw sits further forward than the upper jaw, causing the bottom front teeth to stick out. This condition, which is classed as a type of crossbite, occurs in around 5-10% of the population.

In lots of people, an underbite jaw is barely noticeable, with the bottom teeth resting just slightly in front of the top teeth. In more severe underbite cases, there can be a very noticeable gap between the sets of teeth. No matter the severity of the bite misalignment, underbite correction is generally recommended because of the problems it can lead to if untreated.

What causes an underbite? 

Most cases of underbite teeth are genetic; if at least one parent has (or had) an underbite then the chances of their children having an underbite increase. The condition is also linked to cleft lips and palates. It may also result from certain childhood behaviors such as:

• Thumb sucking
• Tongue thrusting
• Overuse of a pacifier
• Bottle feeding for too long

It may be that the upper jaw is too short and hasn't developed properly or the lower jaw protrudes too far – or a combination of the two.

Do I need underbite correction?

One of the big differences between an underbite and overbite is that some small overbite is natural, whereas no kind of underbite is considered ‘normal’. There are lots of problems that come along with having underbite teeth, and the longer you wait to correct them the harder the treatment may be.

If your child or baby has an underbite, it is best to start treatment early, when their bones are more easily moved. Without treatment, there are lots of potential problems that underbite causes and that your child could face, including:

• Problems with biting and chewing food properly
• Speech issues such as slurring and lisping
• Facial pain because of abnormal strain or pressure on the jaw
• Increased chances of tooth decay
• Worn down and cracked teeth
• A differently shaped face than normal

In the video below, a dentist talks through the problems that children can experience with underbite teeth, why intervention is important, and if orthodontic braces can fix an underbite:

How to fix an underbite

There are a number of ways that have been developed to successfully fix an underbite. Your dentist will explain the best approach for your situation, but below you can find an overview of the most common treatments.

Usually, two or more of these treatments will be combined to provide the most effective, long-term solution for you, your child, your toddler, or your baby with an underbite.

Upper jaw expander

In cases where an underbite jaw is caused by the upper jaw not developing fully, a jaw expander helps it develop to the correct shape. This is a metal device that fits over the back teeth. It gradually pushes out the teeth and expands the palate. Some devices are removable, like a retainer, while others are fixed in place.

This is one of the least noticeable forms of underbite correction; unless you laugh or yawn, nobody is likely to see the top of your mouth or back teeth where it sits. People with underbites who have used a jaw or palate expander say that it can be painful, but some discomfort is expected when you are manipulating the jaw bone. Since jaw bones don’t fuse until around age 12 or 13, starting this treatment at a young age will make things a little bit easier.

A jaw expander is normally used for around one year, but it depends on how much teeth movement is required. Once the treatment is complete, patients have to wear a retainer for a while so that new bone can grow, making the overbite correction permanent.

Underbite headgear

Another method of underbite correction is a reverse pull face mask or headgear. This sounds quite scary, but it is a normal way to fix an underbite. The headgear rests on the forehead and chin and attaches to braces or a retainer using elastic bands to pull the upper jaw slowly into position.

This short animation shows how reverse pull headgear can correct an underbite:

A study has shown this method of underbite correction to be up to 75% effective overall, even more so if treatment is started before the age of ten.

Headgear may be used in conjunction with a chin cap or cup. This device fits over the head, from the crown to the chin, and is designed to reduce the growth of the lower jaw, helping the upper and lower teeth become aligned more quickly.

To get the most benefit, the reverse-pull headgear should be worn as often as possible; certainly every night, and perhaps even during the day. Your child may not mind wearing it while watching TV or doing homework, but wearing it to school and social events is another matter. Still, you should follow your orthodontist’s advice, because using a reverse pull face mask could reduce the need for underbite surgery later on. 

Underbite braces

Along with the methods mentioned above, braces are normally part of underbite treatment. As with braces for other problems, such as overbite, crossbite and open bite teeth, underbite braces will twist, push, and move your teeth into a better alignment.

If you or your child are treated using Medicaid or CHIP, it's most likely that only metal braces will be offered. You can read our full guide to Medicaid dental for more information. As a private patient, however, you will have the option of other, less noticeable options such as clear braces (pictured).

After you have completed your treatment for underbite correction with braces, you will need to wear a retainer to maintain the progress you have made.

Invisalign for underbite

It's also possible to use Invisalign for an underbite in many cases. These clear aligner braces are almost invisible, making them a popular option for people who don't want it to be obvious that they are wearing braces.

It may be possible to treat an underbite with Invisalign braces alone, or they might be incorporated into a course of treatment that includes underbite surgery too.

If you are interested in clear aligners for underbite correction, but Invisalign is just a bit too pricey, you may want to consider at-home options that require no in-office visits with your dentist, thus also rendering them more convenient for many patients.

These aligners are only suitable for mild to moderate cases; have a look at some of the top brands:

If you're not ready to commit to a brand, but want to see if you're eligible for this type of clear aligner, you can take a free Smile Assessment now to get started. You can also read our ALIGNERCO aligners article, NewSmile, Byte, or our Candid teeth aligners article for more information on this type of treatment.

Tooth extraction

Sometimes, an underbite can be caused by having too many teeth in the lower jaw. If this is the case, your dentist will likely advise you have some teeth removed. Extraction may also be necessary to help braces work effectively, as it frees up space for the rest of the teeth to move into.

Tooth extraction is normally done under local anesthetic, although general anesthetic may be used for complicated or multiple extractions. This is a common process which is usually quick, simple and pain-free. The dentist just pushes or twists the tooth to loosen it in the socket, then takes it out. You can read more about the extraction process here.

Underbite jaw surgery

Sometimes the problems with an underbite jaw are quite severe and will require underbite correction surgery. Underbite jaw surgery can involve a few different things, depending on where the surgeon identifies the problem.

The lower jaw might need to be pushed back and repositioned, or the underbite surgery might focus on the upper jaw. Either way, there will small screws and plates inserted around the bones to make sure that they don’t move back. Occasionally, both jaws will need adjustment.

Your surgeon will talk you through what the difference will be in your underbite before and after the surgery. Some common changes include:

• Improved speech
• A different face shape
• Better dental hygiene

This type of surgery isn’t uncommon and you can ask your surgeon or dentist to show you underbite surgery before and after pictures if you are worried about the changes in appearance.

There aren't normally any scars from underbite surgery because all of the cuts are made inside the mouth. The jaws may be wired following the surgery, or an internal frame placed in the mouth, to make sure the bones heal in the correct position.

Patients are recommended to take 2-4 weeks off school or work after underbite jaw surgery. Treatment usually involves the use of braces before or after surgery, or both.

How to fix an underbite at home 

Some of your underbite treatment may happen at home, such as wearing a chin cap or headgear, but do not try to fix this problem without a dental professional. 

Underbite treatment summary

Here is a brief overview of the different types of treatment you may be offered for underbite correction:

Underbite and cleft palate and lip

There is a greater likelihood that babies born with a cleft palate or cleft lip will also have an underbite. because their upper teeth and jaw bone haven't developed properly.

Generally, underbite surgery is needed to correct the problem and is unlikely to be much different from the surgery outlined above. Some surgery to fix issues with the cleft may be done at the same time, or it may be carried out separately. Your Cleft Team will walk you through the treatment, and you can seek support from ACPA too.

Jaw surgery for underbite cost

Your underbite surgery cost will vary depending on the type of insurance you have; through the Child's Health Insurance Program, CHIP, your child may receive free jaw surgery if it's medically necessary. 

Jaw surgery is covered for adults in only about half of the United States, so be sure to call the number on the back of your insurance card to ask about coverage. 

Conclusion

Underbites are a lot less common than overbites; only about 5-10% of people will experience this condition, and it really should be treated in every case. The range of possible ways to fix an underbite means there will be a method that suits you or your child.

When a baby has an underbite diagnosed, a treatment plan can be put into place to ensure the least invasive correction technique is used. The success rates of treatment when done early are really high, and even if surgery is needed, it will make a big difference to your child's oral health and overall wellbeing in the years to come.

FAQS

What is considered a severe underbite?

You may have a severe underbite if you experience pain due to jaw misalignment as well as difficulty chewing, biting or talking. Severe underbite can also have noticeable aesthetic affects. In these cases, you should speak with your dentist or orthodontist about treatment options.

Can braces fix underbite?

Braces are a common treatment for mild to more complex cases of an underbite. If your underbite is quite severe, braces may be used in concert with other methods, including surgery and headgear. 

Can Invisalign fix underbite?

Just like with braces, if you do not have a very bad underbite, invisible braces like Invisalign may be able to help. Clear aligners may also be used alongside other treatment methods in severe cases. 

How do you fix an underbite in adults?

Just like with children, underbite treatment for adults includes braces or jaw surgery. If you want options for underbite treatment without surgery or braces, ask your doctor what is available to you.