A completely or partially broken lower jaw bone, or mandible. An inability to close the mouth or align the teeth properly, as well as a lower jaw that hangs without support, may all indicate a broken jaw. Other symptoms include severe pain in the area; swelling of associated muscles, tendons, and ligaments; or an apparent deformity of the jaw in complete breaks, which may cause the bone segments to separate. Other symptoms include tenderness with light contact and possibly a movable upper jaw, bleeding at the base of the teeth near the fracture site, and numbness. If a broken jaw is suspected, the person should seek immediate medical attention. Using a bandage to immobilize the jaw is the first step in first aid. Diagnosis is made on the basis of a physical examination, special X rays, and possibly a CT (computed tomography) scan. Surgery is often necessary to realign the segments of jaw bone and allow healing. In many cases, the jaw must be wired to the opposing jaw or otherwise immobilized for up to 8 weeks.
A break in the jaw bone usually results from a direct impact. A slight fracture can lead to pain and sensitivity, especially when biting. In more severe cases, jaw movement might be restricted, and numbness could be felt in the lower lip.
Mild fractures typically heal by themselves. However, serious fractures where the bone is out of alignment may necessitate surgical intervention and the jaw being kept immobile.