Underbite

What it is

An underbite, or 'reverse overjet', is when the lower front teeth close in front of the upper front teeth. It can come from the upper jaw sitting too far back, the lower jaw sitting too far forward, the angle of the front teeth, or a mixture of these.

Cochrane reviewers note that an underbite can lead to teasing, difficulty eating and jaw joint problems. Because it often involves how the jaws grow, children with an underbite are usually best assessed by an orthodontist early.

Braces and other appliances used in childhood can improve the bite and the position of the jaws, although researchers do not yet know how long those improvements last. Severe underbites in adults sometimes need a combination of braces and jaw surgery, which the NHS may provide through a hospital service.

Signs and causes

Ways to fix it

The options a dentist may discuss with you, and when each one tends to be used. Which one suits you depends on an examination.

1. Metal braces

   Many underbites involving tooth position; fixed braces are also used before and after jaw surgery.

   Sometimes on the NHSOrthodontics

2. Clear aligners

   Only mild underbites caused mainly by tooth position; problems with the size or position of the jaws usually need other techniques.

   Usually private onlyOrthodontics

3. Retainers

   To hold the result after orthodontic treatment.

   Sometimes on the NHSOrthodontics

What you can do now

• Avoid biting hard foods on the front teeth if they meet edge to edge or wear unevenly
• Mention any jaw pain, clicking or difficulty chewing to your dentist

Preventing it

• There is no reliable way to prevent a jaw-related underbite, but early assessment gives more treatment choices while a child is growing

Products that may help at home

These support good daily care; they don’t replace treatment from a dentist. Some links may be affiliate links.