Underbite is a condition where the lower jaw and the front teeth of the lower jaw are placed in front of the upper jaw and they extend forward from the upper teeth. This can be caused by different factors including the insufficient growth of the upper jaw (when the upper jaw is not developed enough and properly) or if the lower jaw shows overgrowth. The underbite can vary from a mild to a very severe type. When there is a mild underbite the lower front teeth are slightly in front of the upper ones, and they almost meet. But in the cases with severe underbite, the lower front teeth significantly overlap the upper front teeth and there is a large gap between them. The underbite is also known as mandibular prognathism, or Class III malocclusion. The most severe types are a result of a skeletal problem.
The underbite can cause a lot of insecurities for patients because it can greatly affect their appearance and physical looks. This condition can be especially hard for kids. The patients with underbite have a very prominent lower jaw, their chin is protruded together with the lower teeth. Aside from the appearance, the mandibular prognathism can result in difficulties in eating, speaking, breathing. They might also experience problems and pain in the temporomandibular joint, headaches, neck pain and earaches. Because of the difficulty in breathing, some patients breathe through their mouth, which can lead to greater risk of caries, bad breath, and bacterial infections. This condition very often causes a greater loss of teeth enamel and patients might also have trouble in providing proper oral hygiene.
The most common reason for underbite is genetics, in other words, it is a condition that is inherited from parents. The underbite can be caused by an overly-developed mandible, insufficiently developed upper jaw, or even a combination of both.
The treatment depends on the severity of the case. The best results are accomplished with young patients. Orthodontic appliances can be very helpful, especially for the mild cases, but sometimes they need to be combined with surgical treatment for the severe cases. The most common appliances that are used are the “reverse-pull” face mask, upper jaw expander and other fixed appliances depending on the patient.