Open Bite: What It Is, Causes and Treatment

In a normal bite the upper and lower front teeth overlap a little. In an anterior open bite there is a visible gap between them when the back teeth are together. A posterior open bite is rarer and involves a gap between the back teeth on one or both sides.

It is a form of malocclusion. It is the opposite of a deep bite, where the teeth overlap too much. Because the front teeth cannot meet, biting into food with them can be hard, and some people have a lisp.

In children the cause is often a habit that presses on the teeth over time: thumb or finger sucking, a long-used dummy or bottle, or a tongue that pushes forward when swallowing (tongue thrust). Breathing through the mouth because of blocked nose or adenoids can also change the tongue position and jaw growth.

Other causes are the inherited shape of the jaws, with a lower face that grows long and a bite that does not close at the front, and some jaw joint conditions. In adults, a habit-related open bite that was never corrected may stay, and the tongue can be the force that keeps it open.

Treatment depends on the cause and the age. In a child, stopping the habit is the first step, and a habit-breaking appliance or myofunctional (tongue and swallowing) therapy may be advised. If the habit stops early, the bite sometimes closes without braces.

Teenagers and adults with a dental open bite are usually treated with braces or aligners, sometimes with elastics or small anchor screws to bring the front teeth together. A skeletal open bite, where the jaws themselves are the cause, may need jaw surgery combined with braces. Relapse is a known risk, so wearing retainers and addressing the tongue habit matter. An orthodontist can explain which approach fits your case.