Skip to content
Home » Overbite, Underbite, and Crossbite: Causes and Treatment

Overbite, Underbite, and Crossbite: Causes and Treatment

Overbite, underbite, and crossbite are common orthodontic problems that occur due to misalignment of the teeth, usually caused by a combination of genetic and environmental factors.

The alignment of upper and lower jawbones, and the length of your upper jaw, can also be responsible for these irregularities. Treatment options vary from simple measures to complex procedures involving braces or surgery.

The best dental treatment depends on the problem, its severity, and its impact on your health.

With that being said, understanding their differences, causes, and specific treatment methods is the way to get the best possible diagnosis and treatment.

So let’s get to it.

What are Overbite, Underbite, and Crossbite?

While they all involve teeth misalignment and bite issues, you should be aware of their differences.

Overbite

An overbite is a vertical overlap of the upper front teeth over the lower front teeth. If you have an overbite, your upper front teeth may cover all or most of your lower teeth when you bite together normally.

In some cases, an overbite can cause the lower front teeth to bite into the roof of your mouth. In severe cases, this can lead to pain and sores on your palate.

Underbite

An underbite is also called a reverse overbite. It happens when the lower jaw is longer than the upper jaw, or there is no gap between them when you close or bite your teeth.

In this case, your lower front teeth can sometimes come into contact and bite on the inside of your upper lip, cheek, or tongue, making it difficult to close your lips without biting them.

Crossbite

A crossbite is when the upper teeth bite over the lower teeth, which may occur on both sides (bilateral) or one side (unilateral) of your mouth.

Or put simply, the lower front teeth do not align with the upper front teeth.

It occurs when there’s an abnormality in how the upper and lower teeth fit together, most often when a child’s jaws are growing and developing.

What causes Overbite, Underbite, and Crossbite?

The first step in treating any bite disorder is to determine the cause. Once the orthodontist knows why the misalignment occurred, they can treat the problem accordingly.

A common ground that causes overbite, underbite, and crossbite is frequent thumb-sucking during childhood years and genetic inheritance. In contrast, other causes may differ slightly between these three conditions.

Overbite

  • Frequent thumb sucking during childhood.
  • Biting nails one too many times.
  • Genetic condition of teeth misalignment.
  • Use of pacifier after turning three.
  • Losing a tooth or two. This causes the rest of the teeth to shift in response to the gap created.

Underbite

  • Thumb sucking during childhood.
  • Use of pacifiers above the age of 3.
  • Genetic inheritance.
  • Face-related injuries, particularly those affecting the jaw.

Crossbite

  • Genetic condition (skeletal and dental).
  • Mouth-breathing as a habit.
  • Thumb sucking in childhood.
  • Baby teeth didn’t fall out during the relative period.

Symptoms that you have bite disorder

The teeth are held in their sockets by the periodontal ligament. This ligament attaches to both the tooth and its socket. These ligaments compress when you bite down on something, allowing your teeth to move slightly forward and back.

However, if you have a misaligned bite, your teeth can’t make proper contact with each other. This can lead to symptoms such as:

  • Pain in the jaw
  • Changes in speech
  • Headaches
  • Earaches
  • Sensitive teeth
  • Worn enamel
  • Difficulty in chewing or biting into food

What complications do overbite, underbite, and crossbite pose to your mouth?

Malocclusion, or bite disorder, can cause complications with eating, speaking, and other oral functions. However, complications that arise may vary from one bite disorder to another. Here is how they differ.

Overbite

  • May vary in level of severity
  • Overbites more than 5 mm may cause changes in your facial structure
  • Pain in the jaw may develop
  • Headaches
  • Speech difficulties/changes

Underbite

  • Can be mild or severe
  • May lead to TMJ disorder or chronic jaw pain
  • Causing your jaw to lock, click, or pop
  • Headaches
  • Speech difficulties
  • Mouth-breathing
  • Chewing issues
  • Earaches

Crossbite

  • Pain in the jaw
  • Headaches
  • Cause gum recession
  • May lead to teeth loss

How to treat Overbite, Underbite, and Crossbite

After a proper diagnosis, your dentist will consult you on the various treatment options available based on the known causes and how severe your bite disorder may be.

Treatment of an Overbite Condition

Treating an overbite depends on the severity of your overbite and age. In children whose jaw is still developing, orthodontic appliances may be used to help guide the growth of the jaw.

Children with a complete set of permanent teeth may be treated with traditional braces or clear aligners as part of comprehensive orthodontic treatment.

For adults, comprehensive orthodontic treatment is also an option. Surgical intervention may be necessary in severe cases where there’s significant damage to the teeth or gums, such as teeth extraction. This will likely be done by an oral surgeon and an orthodontist.

In general, braces are more effective for treating overbites than clear aligners. Clear aligners are most effective for minor issues because they aren’t as strong as metal braces.

However, a skilled orthodontist can treat mild to moderate overbites with clear aligners just as effectively as they can with metal braces.

How to Treat Underbite

Treatment for an underbite will depend on several factors like tooth alignment, age, and overall health.

For crowded lower anterior teeth, it would be necessary to possibly extract a tooth and straighten the remaining by using braces or Invisalign to get that alignment back to normal.

Surgery is usually needed for more severe underbites. A surgeon will detach the jawbone and rejoin it in a different position. This treatment can also help with an overbite. In some cases, however, surgery isn’t necessary.

For example, if you have an overbite, but your molars are properly aligned, a dental professional will push the front teeth back into place and reshape them without surgery.

Crossbite: Treatment

Crossbites can be treated in several different ways, depending on the severity of the problem.

Braces are the most common treatment option for adults and children.

Braces apply continuous pressure to your teeth over time and move them into the correct position. In some cases, an orthodontist may recommend a palate expander to widen the roof of the mouth before braces are attached to create more room for teeth.

An orthodontist may also recommend surgery to correct a crossbite if braces don’t work or aren’t an option. Surgery is often used in conjunction with braces when additional help is needed to fix extreme crossbite cases.

What happens if you leave your bite disorders untreated?

It’s easy to take our teeth for granted, but the effects of a bad bite can be far-reaching. If your teeth don’t meet correctly, you may develop severe malocclusion. This can have repercussions for your oral and overall health. Leaving them untreated may lead to:

  • Further complications that affect your overall health
  • Tooth decay
  • Losing teeth
  • Gum diseases
  • Chewing and speaking disorder
  • Damage of tooth enamel
  • Further jaw issues

The bottom line

To summarize, you can overcome bite issues with the right treatment plan. If you have an overbite, underbite, or crossbite, the best treatment option is to see a dentist who can properly diagnose and treat your condition.

There are multiple treatments available for each of these issues. Therefore, seeing a dentist who can narrow down the most appropriate solution for your specific case is crucial.

Adopting proper oral health habits early is a great way to prevent bite-related issues. The rule of thumb is to brush twice daily, floss at least once per day, and see the dentist for routine cleanings every six months.

Sources:

  • European Journal of Dentistry. The genetic basis of facial skeletal characteristics and its relation with orthodontics. 2012 Jul; 6(3): 340–345.
  • Mayo Clinic. TMJ disorders.
  • International Journal of Environmental Research and Public Health. Environmental Factors Associated with Malocclusion in Children Population from Mining Areas, Western Romania. 2019 Sep; 16(18): 3383.
  • European Journal of Orthodontics. Dental arch width, overbite, and overjet in a Finnish population with normal occlusion between 7 and 32 years. Volume 34, Issue 4, August 2012
  • Mayo Clinic. Jaw surgery.