Open-bite is a condition where the top and bottom sets of teeth do not meet at all, leaving a normally elliptical gap – an open-bite. As with tooth crowding, open-bite is often linked to certain behaviours in infancy, such as thumb sucking, tongue thrust (where the tongue sticks out over the lower front teeth when swallowing or speaking, or simply rests there), or any other repetitive behaviour involving sucking or chewing an object, like a pencil.
The condition is most likely to be caused by genetic (i.e. inherited) factors relating to skeletal structure of the skull. Over long use of either dummies or feeding bottles can also contribute to the development of open-bite.
Open-bite can affect a person's smile, and can also cause a lisp in speech, both of which may contribute to self-esteem issues.
Open-bite can be difficult to correct and is best addressed as soon as it appears, which is often at a young age, before adult teeth form, when the development of the jawbone and positioning of the teeth can be more easily controlled. Treatment depends very much on what is causing the open-bite – it may be possible to treat using braces or Invisalign, or other orthodontics appliances, or simply by discouraging the behaviour that is causing the problem. In severe cases surgery may be required, but this is generally only after full development of the adult teeth and jaw structure is complete.