What are the causes and risks of the injury? A dislocated jaw can occur when the mandible, the lower bone of the jaw, is displaced from the temporomandibular joint, or TMJ. The TMJ is the joint between the jaw and the skull. When the jaw is broken, it usually breaks in 2 areas: at the site of injury and on the opposite side of the jaw. Another bone of the jaw is the maxilla, which contains the upper teeth. When this bone is broken, there are usually other fractures in the face.
The most common causes of a broken or dislocated jaw are sports injuries, industrial accidents, and motor vehicle accidents. A person can also get a dislocated or broken jaw by being punched in the face.
What can be done to prevent the injury? Most injuries occur when the proper protective gear is not worn. Sports safety guidelines should be followed for children, adolescents, and adults.
It is also important to stay alert and attentive during high-risk sports, while driving a motor vehicle, and while at work. Medications that slow reflexes or cause drowsiness increase the risk of accidents during these activities. Illegal drugs and alcohol should be also be avoided.
How is the injury recognised? The doctor will often suspect a broken or dislocated jaw during the physical examination of the person. An X-ray can be done to identify the broken bone or dislocation.
What are the treatments for the injury? A broken or dislocated jaw requires immediate medical attention. Some people with jaw fractures will have bleeding and difficulty breathing. Other first aid steps include the following:
Check for signs of circulation, such as normal breathing, coughing, or movement in response to stimulation.
Contact the emergency medical system immediately.
Start cardiopulmonary resuscitation, or CPR, if the person stops breathing. Use 15 chest compressions for every 2 mouth-to-mouth rescue breaths.
Do not try to relocate or move the jaw. Until proper medical care can be given, the rescuer or assistant should use his or her hands to gently support the injured person's jaw.
A doctor or dentist can move a dislocated jaw back into place. Sometimes this requires sedating the person with a fairly strong medication.
Occasionally, even with anaesthesia, the jaw cannot be moved back into its original position. If this is the case, surgery may be needed to fasten the joints.
After the jaw is moved, it will need to be held in a steady position for a significant amount of time. This is usually done by either wiring the jaw shut or by taping around the outside of the head to keep the jaw from opening widely. The tape or wires are usually left in place for 6 weeks.
What are the side effects of the treatments? Treatment for a dislocated or broken jaw is often painful. If wiring is done, a person could vomit and choke on the vomited material. For this reason, people are nearly always given wire cutters.
Infection of the gums and bone where the wires are placed is also possible. A lesser concern is weight loss and lack of nutrition because of the difficulty of chewing food while the jaws are wired shut. High-kilojoule shakes and foods that do not require chewing can be used.
What happens after treatment for the injury? After the jaw has been repaired, the person should be particularly careful when yawning and sneezing. If the jaw is broken, soft foods should be eaten.
It is important to make sure that risky situations are avoided to prevent the injury from happening again. Once the jaw has healed and the wires have been removed, some people will experience pain in their temporomandibular joint, or TMJ. A doctor or dentist can prescribe analgesics and exercises to help reduce pain.
Author: Reviewer: eknowhow Medical Review Panel Editor: Dr John Hearne Last Updated: 17/10/2004 Contributors Potential conflict of interest information for reviewers available on request