Causes of Underbite and Correction Methods
A smile doesn’t just boost your confidence – it can markedly improve your quality of life. However, dental conditions that affect the alignment of your jaw and teeth can leave you feeling self-conscious and disheartened.
An underbite is one such dental condition – although thankfully it’s treatable. We explore the causes and correction methods for underbite in more detail below.
What is an underbite?
An underbite is a misalignment of the jaw that causes the lower teeth to protrude beyond the upper teeth. Also known as a Class III malocclusion or ‘reverse-bite’, underbites affect just 5% to 10% of the population – as opposed to the more common protrusive bite, which is colloquially referred to as an “overbite”. They range in severity from mild cases that are almost unnoticeable, to severe cases where the lower jaw extends out far beyond the upper jaw.
While it’s possible to live with a mild underbite, more severe cases can contribute to more serious problems. These include speech, biting and chewing difficulties, pain and discomfort in the mouth and jaw and excessive tooth wear. Some underbites can damage the tooth enamel and increase the likelihood of chips and breakages of the front teeth.
The good news? Orthodontic treatment to correct an underbite is highly effective and in many cases, underbites can be fixed without surgery.
The causes of underbite vary and may include:
- Genetics. Did you know that underbites are most commonly inherited? Genetics help determine the shape and size of your teeth and jaw, meaning that overcrowded teeth or a misaligned jaw are likely inherited from other family members. If your underbite is due to genetics, prevention is not generally possible.
- Injury. Serious facial injuries can cause lasting damage to the jaw. While it’s possible to surgically repair broken jaw bones, teeth may not always align post-surgery. This can potentially lead to an underbite.
- Tumours. Although quite uncommon, tumours of the mouth or jawbone can cause an underbite by affecting the growth or alignment of the jaw.
In a word, no. Underbites (and overbite) are most commonly caused by a genetic misalignment of the jaw, meaning that your wisdom teeth won’t lead to underbite. While underbites may worsen with adolescent growth and later teenage growth – coinciding with the eruption of your wisdom teeth – the two isses are actually not associated with each other.
The sooner the better. In many cases, orthodontic treatment to correct an underbite should be started in childhood, while the jaw bones are still malleable and may be more easily coerced into alignment. Early diagnosis with a specialist orthodontist can provide the appropriate information and best advice to manage an underbite problem.
Do children outgrow underbites?
Unfortunately, children do not outgrow underbites. As underbites are usually inherited, it’s unlikely that when a child’s adult teeth come through, the underbite will disappear.
The appearance of an underbite may actually worsen during puberty, particularly during the growth spurt. That is, the underbite can become larger, the lower jaw and chin appearing more protrusive, and the profile becoming more concave. This is why we recommend seeking early treatment as certain cases can be successfully intercepted.
Can braces fix an underbite?
Yes, braces or clear aligners can be an effective method of treatment for an underbite, particularly for milder cases. An orthodontist can provide an accurate diagnosis and then determine the relevant treatment options available for your individual case. The severity of the diagnosed “underbite” will directly influence the treatment recommendations. This is why it is vitally important to see a specialist orthodontist, as an inaccurate diagnosis often leads to incomplete or ineffective treatment.
Treatment methods depend on the age of the patient and the severity of their underbite, though in most cases mild to moderate underbites can be fixed without surgery. The most common methods to correct an underbite include:
- An upper jaw expander. This may be recommended if the upper jaw is also small in width. Fitted across the patient’s palate, the upper jaw expander works by gradually widening the jaw so that the lower teeth match better with the upper teeth.
- The ‘reverse-pull’ headgear. This type of headgear can be used to pull the upper jaw forward and works more effectively for patients under the age of 10.
- Braces or clear aligners. Suitable for both children and adults, braces or clear aligners such as Invisalign®, Spark® and 3M Clarity can be an effective treatment method for underbite, especially if orthodontic elastics are worn.
- Tooth extraction. Where appropriate, extracting carefully selected teeth can help correct underbite in mild to moderate cases.
- Surgery. In adults with severe underbite, orthognathic jaw surgery may be required to align the upper and lower jaws into their ideal positions. The surgery is generally very predictable and is considered low risk. When appropriate, a referral to an maxillofacial surgeon will be provided by your specialist orthodontist.
The key to correctly and effectively managing underbites is an early diagnosis by a knowledgeable specialist orthodontist. Click here to search for an orthodontist near you now.