Underbite: Causes, Correction, and More

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Want to learn more about underbite, what causes it and how to correct it? If the answer is yes, then this article is for you.

Smiling doesn’t only make you feel good; it can actually improve your quality of life and trick your brain to be happy. This is because smiling doesn’t only offers a boost in your mood, it also helps the body release endorphins and cortisol, both hormones provide tons of benefits, from reduced blood pressure, pain, and stress, and improved heart health, helping boost the immune system, and increase endurance. The challenge about smiling however is many people are ashamed to show their teeth. Malocclusions like underbite are keeping them from smiling and feeling genuinely happy and confident.

So how do you fix this? Here is everything you need to know about underbite, its causes, health issues they bring, and treatments.

Everything you need to know about underbite

What is an underbite?

An underbite is a medical term used to describe a dental condition where the lower teeth overlap or extend farther outward than the upper teeth. It is actually a condition Class III malocclusion or prognathism.

Not all underbites are the same; there are different levels of severity ranging from mild underbite to severe underbite. Mild cases can be difficult to notice from the outside. This is because the misalignment is mostly limited to the upper and lower rows of teeth (upper and lower teeth almost meet). Severe cases, on the other hand, cause the jaw to protrude far outward, making it easily noticeable. This is because the teeth don’t meet at all because of jaw misalignment. This malocclusion creates a bulldog-like look on the face, making people self-conscious about their mouths.

Effects of underbite on your health

Underbites are more than just cosmetic issues. While many may be able to live with mild cases, severe cases can cause oral health problems. Bite alignment problems like underbite can cause speech difficulties, mouth breathing, irritation in the mouth, and difficulty biting and chewing food.

Severe jaw misalignment can cause mouth and facial pain, leading to wear to either or both upper jaw or lower jaw, causing chronic jaw pain. A misaligned bite can also cause wear and tear to upper and lower teeth, making teeth more prone to breakage, and chipping, and increasing the risk of tooth decay due to worn enamel.

Depending on the severity, undertbites can also cause:

• Temporomandibular joint disorder (TMJ)

• Sleep apnea (snoring, and breathing difficulties during sleep)

• Constant headaches and earaches

• Chronic mouth breathing

• Halitosis (bad breath)

• Bacterial infections

• Emotional stress (especially among kids due to bullying)

Moreover, undetbites can definitely affect someone’s self-confidence and social life.

Underbite and chronic sleep apnea

Not only can the malocclusion take a toll on anyone mentally, it can also negatively affect your sleep, as it is one of the most common factors that cause sleep apnea or chronic snoring.

Sleep apnea happens when normal breathing is interrupted during sleep. This means not enough oxygen goes into the body, causing you to not sleep well and feel tired and fatigued during the day, even after a full night of sleep.

Underbite and Temporomandibular Joint Disorder (TMJD or TMD)

The temporomandibular joints are the joints that connect your lower jaw to the base of your skull. Bite alignment problems like underbite can cause unnecessary wear to these joints, leading to stress on the muscles and cartilage that surrounds them. This can cause clicking and popping sounds in the jaw joint, accompanied by pain, swelling, and inflammation.

What is the cause of underbite?

There are several factors that could lead to an underbite, including genetics, childhood habits, injury, and even tumors. The biggest factor, however, is the way the teeth grow.

In perfectly aligned teeth, the teeth grow in a way that the upper set of teeth grows a little over the lower set of teeth. The upper and lower molars should fit into one another. This setup keeps you from biting your own lips, tongue, and inside of your cheeks.

Factors that contribute to underbite include:

Childhood habits:

• Using pacifier more than 3 years of age

• Thumb sucking

• Pushing teeth using the tongue

• Long-term use of feeding bottle (beyond infant years)

Genetics:

Some people are more predisposed to develop various types of malocclusions like an underbite. This is because genetics plays a role in the development and shape of one’s jaw. Some people are also born with teeth too close together or not fitting together properly due to smaller or abnormally-shaped mouths. Cleft lip or palate is also a contributory factor.

Injury

Severe trauma to the mouth and head that leads to injury can also cause the jaw to move in the wrong direction.

Tumors

Tumors in the jawbone can cause the teeth and the jaw to move in the wrong direction, resulting in malocclusions like an underbite.

Underbite Correction Methods

As with other malocclusions and bite-related problems, underbite correction starts with a consultation with your dental professional. Depending on the complexity and severity of your case, the correction can be administered by a dentist or an orthodontist.

Dentists cover a broad range of oral health problems, such as broken or missing teeth, cavities, gum disease, etc. While orthodontists are dentists with specialized training in orthodontic treatment that focuses on tooth and jaw alignment.

Dental experts suggest that malocclusions like underbites are best treated early (child’s age). As a matter of fact, dental professionals can start correcting underbites in children as early as possible, since younger ones have bones and palates that are easier to manipulate and correct.

Depending on the overbite, some may require one or a combination of the following orthodontic treatments:

Braces

Braces are the gold standard of orthodontic treatment. It can fix a wide range of malocclusion and bite alignment problems, from underbite, overbite, overjet, overcrowding, etc. It can even fix problems concerning upper and lower jaws.

While the best age for braces is between ages 9 to 14, adults can also get their malocclusions fixed with braces.

There are different types of braces to choose from, such as traditional metal braces, ceramic, self-litigating, lingual, and the newest in the orthodontic market – clear braces. Clear braces like Invisalign are virtually invisible, making them more aesthetically pleasing than their conventional counterpart. Plus, they are removable, making it easy to eat, drink, and clean your teeth during treatment.

After braces treatment, however, come retainers. This is probably the least expensive part of the treatment.

Reverse pull face mask

The appliance resembles a braces headgear, designed for children 10 years old or younger. This is the stage where their bones haven’t fully fused yet. It wraps around the head of the child; using the metal bands fastened to the upper backside of the teeth, it pulls the upper jaw back to the right position. A chin cup is placed to keep the mask secured in its place.

This device is only as effective as the patient’s compliance. Thus, it must be worn as much as possible, even during sleeping.

Upper jaw expander

As its name suggests, this device expands the upper jaw. Orthodontists fit this device across the palate using a wireframe. Each night, the patient will have to use the special key provided to turn and “widen” the expander. Upper jaw expander correct underbite problems by gradually causing the upper jaw to widen until the lower set of teeth no longer closes against the outside of the upper set of teeth.

This device is usually worn for about 12 months before replacing it with a retainer to encourage proper bone growth. Like the reverse-pull face mask, this device works best with children whose bones are still growing and forming.

Tooth extraction

Sometimes, the best underbite correction method is to remove a tooth out. Tooth extraction is usually used for patients with too many lower teeth that cause protrusion in the lower jaw. This procedure can be a one-off or used along with other methods.

Jaw surgery

Depending on the specifics of the underbite, jaw surgery may be used to correct the malocclusion. Your oral and maxillofacial surgeon may prescribe any of these procedures:

• Orthognathic jaw surgery – this form of surgery aims to correct irregularities in the jawbone and realign both the jaws and teeth to improve the way they look and work. Sometimes, it involves the removal of a part of the lower jawbone to fix the protruding jaw. From there, surgeons can modify the jaw bone and allow it to reposition the lower teeth further back. This surgery may also improve one’s facial appearance.

• Le Fort III Osteotomy – usually used for cases where the face appears to have sunk above the lower jaw, this procedure moves the entire face forward. This procedure can also change the appearance and function of the jaw.

An underbite can easily affect your quality of life. Fortunately, there are many ways to fix it. Talk to your dentist or orthodontist today and get that beautiful smile you deserve!

Dr Febin Mary George - Editor

With more than 10 years as a dental surgeon, Dr Febin Mary George is passionate about educating consumers around the world to help look after their teeth.

She completed her Bachelor of Surgery at the Century Institute of Dental Science and Research Centre in 2010.

Alongside editing the International Journal of Dental Clinics she has also written for major publications including Thrive Global.