The mandible is the lower jaw bone. It contains the teeth and is part of the joint that opens, closes and laterally moves the lower jaw. This joint is called the temporomandibular joint. The part of the mandible associated with the temporomandibular joint is the condyle. Like other parts of the mandible the condyle can be fractured on one or both sides, causing an inability to properly align the teeth or to open and close the jaw.
The mandible is a curved bone that extends from one side of the face to the other. On either side are the condyles that act as the “ball” of the joint into the glenoid fossa. This joint is very near the ear canal. There is a small process near the condyle called the coronoid process, which stabilizes some muscles and tendons. The ramus is the part of the mandible that runs down the side of the face. It is relatively thin compared to the body of the mandible. The body of the mandible holds the teeth, and is thick and relatively strong. The symphysis is the non-moving connection between the two halves of the mandible. Fractures can occur along this line.
In one study of patients who had about 1,500 mandibular fractures, it was noted that most fractures occurred between the ages of 20-29 years and that there was a 3:1 distribution of males to females. Perhaps this is because altercations were the most common reason behind getting a mandibular fracture. The second most common reason was motor vehicle accidents, which lend themselves to severe fractures. Falls accounted for another large percentage of fractures of the mandible.
Mandibular fractures can usually be identified using plain film x-rays, although a CT scan of the facial region generally does better when it comes to identifying subtle fractures or complex fractures. MRI scans of the facial area show good soft tissue images and can identify areas of tissue damage.
The treatment of mandibular fractures depends on the site of the fracture and on whether or not it is dislocated. In the emergency department, doctors need to pay attention to the patient’s airway as there can be swelling that makes the movement of air difficult. If oropharyngeal airway management is too difficult because of bleeding or advanced swelling, a cricothyrotomy might need to be done. Once the airway is stable, the facial bones can be assessed along with the rest of the body to make sure no other injuries exist.
When it comes to repair of these types of fractures, a maxillofacial surgeon or ENT specialist is the type of doctor necessary to do open surgery to put plates and screws where necessary in order to keep the bones in place for healing. Sometimes the jaw needs to be wired shut in order to make sure that the teeth are in good alignment throughout the healing process.