K09: Cysts of oral region, not elsewhere classified

K09.1: Developmental (nonodontogenic) cysts of oral region

The mouth area includes the jaw, the soft tissue in the mouth, and the teeth. The jaw consists of the upper jaw and lower jaw. The upper jaw bone is located above the mouth and forms the roof of the oral cavity. The lower jaw bone is located below and to the side of the mouth. In the center of the lower jaw is the chin. To the side, the lower jaw bone extends to below the ears. The mandibular joint is located there.

Cavities can develop in the jaw bone or in the tissue in the mouth area. The cavities can be filled with fluid. Cavities can develop due to problems with how the jaw or head develops.

If the cavities are very large, problems may occur. You may feel a swelling, for example. You may also have problems when swallowing or speaking. If the cavities are very large, they may also press on the surrounding tissue or on nerves. This can then be painful. The teeth may also be displaced, or the cavities can damage the jaw bone.