Overbite and Overjet

What is an overbite and what is an overjet?
The overbite is the name given to the vertical overlap of the upper teeth and jaw over the bottom teeth and


jaw. This is the position in which the teeth and jaws sit at rest.

Ideally, the top jaw and set of anterior (or “front”) teeth should mildly overlap the lower jaw and teeth beneath, with the premolar and molars gently closed together at the back. This evenly distributes the biting and grinding load of the teeth and jaws. A problematic, or “deep”, overbite is one where the top jaw and teeth sit too deeply over the opposing teeth.

The overjet is the name given to the horizontal overlap of the upper jaw and front


teeth out across the bottom jaw. A problematic overjet is one where the upper teeth and jaw sit too far forward over the bottom.

What causes the overbite and overjet?

A deep overbite or problematic overjet are often hereditary, but may also be the result of:

  • The development or under-development of the jaw and dentition (“teeth”)
  • Tongue-thrusting, where your tongue pushes forward against the front teeth when you swallow
  • Mouth-breathing
  • Habits such as thumb-sucking
  • Misuse of dummies or baby bottles while the mouth and teeth were developing

What impact do they have?
While a deep overbite or a problematic overjet may have a cosmetic impact on the sufferer, they may also affect your ability to bite, chew, comfortably close your lips, and even talk. They may also put undue pressure on one or more of your jaw joints and cause premature tooth wear, and even dental trauma.

How are they treated?
A deep overbite and overjet can be treated in several ways; more severe cases may be best treated with a combined surgical and orthodontic approach, where others may be treated with the removal of teeth and orthodontic treatment, or simply orthodontic treatment alone.

To find out more about overbites and overjets, and your treatment options, contact us today to organise a free consultation with Specialist Orthodontist, Dr David Austin.