Underbite

A misaligned bite can make biting or chewing uncomfortable, alter facial appearance, and sometimes affect speech. The lower teeth may meet the upper teeth in an unusual position rather than fitting into the opposing molar grooves.

Underbites are often inherited. A difference between upper and lower jaw size, or between jaw and tooth size, can produce the forward lower-jaw relationship.

Thumb sucking, tongue thrusting, prolonged bottle use, extra or impacted teeth, early tooth loss, and some birth differences can also contribute to abnormal bite patterns.

Bite relationships can be assessed through primary, mixed, adolescent, and adult dentitions. Changes in eruption, arch length, and jaw growth matter when a developing underbite is followed over time.

Family tendency, jaw-size differences, cleft lip or palate, tooth crowding, and habits that push the tongue forward are recognised contributors to malocclusion.

The assessment checks how the back teeth come together and how the upper and lower jaws relate. Dental, head, skull, or facial X-rays and models of the teeth may be used to diagnose a bite problem.

Braces, fixed appliances, or clear aligners can move teeth. Crowding may require removal of teeth, and rare jaw-size problems may need surgical reshaping that is stabilised with wires, plates, or screws.

Correcting an underbite can involve braces or aligners, tooth removal, repair of irregular teeth, or rarely jaw surgery. The treatment method and amount of correction shape the work involved.

Moderate or severe malocclusion can strain teeth, jaws, and muscles. It can also make cleaning harder, increasing the risk of tooth decay and gum disease; orthodontic appliances can irritate gums and make chewing or speaking difficult during treatment.

Many underbites cannot be prevented, particularly when jaw growth is inherited. Controlling thumb sucking or tongue thrusting and addressing bite changes early can make correction quicker and more successful.