What is an overbite? Causes, types, and correction treatment

Dani Dinkel

Written by Dani Dinkel RDH

The term “malocclusion” means bite misalignment or crooked teeth. Overbite is a common type of occlusion deviation. It occurs when your upper teeth stick out beyond the lower front ones. The overlap varies from slight to severe and can cause significant health complications.

In this article, we discuss the causes of overbite and preventive measures for stopping the development of malocclusion. You’ll also find out how the overbite affects the body and what are the methods of treatment.

Overbite: definition and types

Lingual braces

Picture by Authority Dental under CC 2.0 license

Overbite is also called buck teeth or deep bite. It’s a difference in jawbone alignment, when upper teeth excessively overlap lower jaw, placed too far in the back. It’s often visible at a glance in facial structure. Apart from appearance, symptoms include:

  • difficulty fully opening or closing the mouth,
  • speech defects,
  • discomfort while eating, and
  • jaw pain.

If you wonder whether you have an overbite, look in the mirror while biting down. If the majority of your lower teeth are covered by the upper ones, or there is a horizontal distance bigger than 2mm, that’s the sign that your jaw is misaligned. A dentist will take dental X-rays to examine your bite details and refer you to an orthodontist if needed.

There are two types of overbites, depending on the root cause.

Skeletal overbite

Skeletal overbite occurs due to the irregular size and shape of the jaw and teeth. It’s genetic.

Dental overbite

Dental overbite is caused by an external interruption of dental development, usually by childhood habits. It can be combined with skeletal malocclusion, worsening the inherited condition.

Orthodontists also divide the overbites measuring the severity of the defect:

  • normal: 1 to 3 mm
  • deep: 4 to 8 mm
  • severe: 9 mm or more.

The bigger overlap between the top and bottom teeth, the more complex treatment is required.

What causes an overbite?

There are several reasons why overbites occur. Many of them start in early childhood, or even earlier, as they’re written in our genes.

Genetics

The shape and development of bones are inherited from our parents and relatives. According to studies, overbite is mostly determined by genetic factors. The lower jaw can be too small, too big, or misshapen. That causes teeth to crowd, misalign, or drift away.

Habits in childhood

Even small behaviors during early childhood can have a significant influence on a child’s development. If nonnutritive sucking behavior or pushing on the back of the teeth continues past the age of 3, it can lead to a dental overbite. Among the habits causing overbite are:

  • thumb sucking,
  • tongue thrusting,
  • lip sucking, and
  • excessive use of a pacifier.

Oral health

Tooth loss creates more space for remaining teeth, sometimes leading to changes in their alignment. On the other hand, having extra teeth or impacted teeth causes crowding, which can similarly result in misalignment.

Some dental habits, such as nail-biting, chewing on hard objects, or teeth grinding can provoke overbite regardless of age.

How does an overbite affect the body?

If left untreated, an overbite can deepen and lead to severe health complications. Some of them may be permanent. The most common problems are:

Jaw pain and headaches

Teeth misalignment puts a lot of pressure on the temporomandibular joint and muscles (jaw area), especially during eating. Over time, it can cause TMJ dysfunction, which symptoms include jaw pain and tenderness, a clicking, popping, or locking jaw. Discomfort can spread to the neck, face, and head area, provoking stiffness and headaches.

TMJ is a hinge joint that connects the lower jaw to the rest of the skull. When it’s affected, you may also experience pain while chewing and swallowing, or difficulty with fully opening or closing your mouth.

Alterations in facial appearance

If left untreated, an overbite can make structural changes in your mouth that alter also your physiognomy. Apart from lower self-esteem, this may lead to speech impediments or even breathing issues.

This also significantly affects your teeth, as they become crooked, crowded, or spaced too far from each other. All those conditions make you more susceptible to various dental problems.

Tooth decay

Due to the abnormal position of teeth, their protective layer wears off much faster. The holes in the enamel are a perfect environment for cavity-causing bacteria.

Gum disease

In a deep or severe overbite, lower teeth often touch the gumline of the upper front teeth. Gum tissue tends to recess at the point of contact, exposing the tooth’s root. This can result in gingivitis or periodontal disease.

How to fix an overbite?

The treatment method depends on severity of the overbite. Severe conditions usually require professional intervention and therapy. Some light cases don’t need to be fixed at all, while others should be treated to avoid future complications. Many people choose to fix their overbite for cosmetic reasons.

Braces

Self-ligating braces

Picture by Authority Dental under CC 2.0 license

Traditional, fixed braces are the most common way to treat an overbite. First, the metal wire helps to straighten each tooth that’s not in the right position. Then, with the use of coils and bands, consistent pressure is added to align the upper and lower jaw.

This treatment requires from 1 to 3 years of wearing braces. It’s a very effective method that can correct even severe overbite, as well as other misalignments.

Invisalign

Invisalign full treatment

Picture by Authority Dental under CC 2.0 license

Many people prefer Invisalign treatment for aesthetic reasons. However, they can correct only minor overbites, not severe malocclusions.

In order to achieve desired results, you need to wear Invisalign for at least 22 hours per day, removing it only for eating or brushing.

Surgery

If the jaw misalignment is very severe, surgery may be necessary. The oral surgeon will reposition the jawbones to achieve the required bite.

Jaw surgery is always combined with braces. You will have to wear them for about 12 months prior to the procedure, to move the teeth into the right position. After the surgery, you’ll need braces to maintain the new alignment.

Palate expansion

When the problem is caused by the too-small jaw, a palate expander may help. It’s an orthodontic appliance that helps to separate maxillary bones and widen the entire upper jaw.

The palate expander needs to be worn for about a year to achieve the right shape, and then another couple of months to keep the bones from relapsing. This treatment works best for children, whose jaws are still growing.

FAQ

How can I prevent overbite?

Keep your children from developing harmful habits, such as thumb sucking or excessive use of a pacifier. Schedule their first dental visit by age 1. As an adult, don’t chew on hard objects such as pencils, and wear a nightguard to avoid teeth grinding at night. Don't forget about regular dental check-ups to keep an eye on changes in your mouth.

Is an overbite bad?

You don’t have to worry about minor overbite. However moderate or severe misalignment can cause various oral problems, from gum recession and tooth decay to chronic headaches and pain during chewing.

Does overbite get worse with age?

Overbite, especially caused by genetics, tends to deepen with time. Small habits, such as thumb sucking or pushing the tongue against teeth can easily exacerbate this condition.

It’s best to visit the orthodontist before the child is 8 years old. At this stage, correction is much easier.

How long does it take to fix an overbite?

The answer will vary depending on the severity of the case. Usually, it takes about 2 to 3 years, but deep overbites may require longer treatment. Similarly, minor problems can be fixed in a shorter amount of time.

Does fixing overbite change face shape?

If you suffer from a severe overbite, the alteration will be visible in your face structure. This can be particularly visible when you decide on surgery. Usually, fixing an overbite changes appearance for the better, improving the harmony between your facial features.

References

  1. Buck teeth: Correct them once in early adolescence - ScienceDaily
  2. Deep overbite correction: Biomechanics and clinical implications - ScienceDirect
  3. Influence of heritability on occlusal traits: a systematic review of studies in twins - SpringerOpen
  4. Predictability of overbite control with the Invisalign appliance - ScienceDirect
  5. Postretention assessment of deep overbite correction in Class II Division 2 malocclusion - PubMed