Broken or dislocated jaw

A broken jaw is a fracture of the jawbone. Most broken jaws involve the mandible, the U-shaped lower jawbone that holds the lower teeth. Fractures of the upper jaw are usually considered part of a more complex facial injury and may affect the nose, eye sockets, or skull.

A dislocated jaw is different. It occurs when one or both rounded ends of the lower jaw move out of their normal position at the temporomandibular joints, or TMJs. These joints sit just in front of the ears. In the most common type of dislocation, the jaw moves forward and becomes stuck, leaving the mouth open.

Both injuries can affect breathing, eating, speaking, and the way the teeth fit together. A fracture may also injure teeth, facial nerves, or nearby soft tissue. A dislocation can cause severe muscle spasm and may become harder to correct if treatment is delayed.

A suspected broken or dislocated jaw needs prompt medical assessment. Do not try to straighten or push the jaw back into place yourself.

Call emergency services if the person has:

• Trouble breathing, choking, or rapidly increasing swelling
• Heavy bleeding that does not stop with gentle pressure
• Loss of consciousness, confusion, seizure, or repeated vomiting
• A severe head or neck injury
• An object lodged in the mouth or airway

If these signs are not present, seek urgent same-day care for a jaw that looks deformed, will not open or close normally, or has become painful after an injury.

Symptoms depend on whether the jaw is fractured or dislocated. More than one injury can occur at the same time.

Possible signs of a broken lower jaw include:

• Pain that becomes worse with speaking, chewing, or moving the jaw
• Swelling, bruising, or tenderness along the jaw
• Teeth that no longer meet in their usual position
• Loose, broken, or missing teeth
• Bleeding from the mouth or around the gums
• Difficulty opening or closing the mouth
• A change in the shape or movement of the jaw
• Numbness of the lower lip or chin
• A cut inside the mouth or a gap in the gum near a fracture

A fracture can communicate with the mouth through a tooth socket or gum injury even when there is no cut on the skin. Clinicians may call this an open fracture because bacteria from the mouth can reach the broken bone.

With a dislocated jaw, the mouth is often stuck open. The person may be unable to bring the teeth together or may have trouble speaking and swallowing saliva. The lower jaw may look pushed forward or shifted to one side. Pain is often felt in front of the ear, and the jaw muscles may tighten or spasm.

Some fractures are not obvious from appearance alone. A new change in the bite—the way the upper and lower teeth fit together—is an important reason to seek assessment after facial trauma.

Most jaw fractures result from a direct impact. Common causes include motor vehicle or bicycle crashes, falls, sports injuries, workplace injuries, and physical assault. A force strong enough to break the jaw may also cause injuries to the brain, neck, eyes, nose, or other facial bones.

Less commonly, a jaw weakened by a tumor, bone infection, or another bone disorder can fracture with less force than expected. A clinician may investigate an underlying condition when the injury does not match the severity of the fracture.

A jaw dislocation can occur after the mouth opens very widely. It may happen while yawning, biting into a large piece of food, vomiting, or during a dental or medical procedure. A blow to the jaw can also cause dislocation and may produce a fracture at the same time.

Previous dislocation increases the chance of another episode. Joint looseness, certain connective tissue disorders, abnormal jaw anatomy, and conditions or medicines that cause involuntary muscle movements may also increase risk. However, a dislocation can occur without any known risk factor.

The first priority after significant facial trauma is to check breathing, circulation, and possible head or neck injury. A cervical collar or other neck precautions may be used until a spinal injury has been considered.

The clinician will ask how the injury happened and whether the bite feels different. They will examine the face and mouth for swelling, wounds, bleeding, loose teeth, abnormal movement, and tenderness. Sensation in the lower lip and chin may be checked because a nerve runs through the lower jawbone.

Imaging is often needed for a suspected fracture. Computed tomography, or CT, creates detailed cross-sectional images and can show the number, position, and complexity of facial fractures. Panoramic or other dental X-rays may be useful for selected lower-jaw injuries. The choice of imaging depends on the examination, injury mechanism, and available equipment.

A typical non-traumatic jaw dislocation can sometimes be identified from the jaw’s position and the inability to close the mouth. Imaging may be obtained before reduction if the cause was trauma, the diagnosis is uncertain, a fracture is possible, or the joint anatomy needs further evaluation.

Until medical help is available, keep the jaw as still as reasonably possible. A person can gently support it with a hand or soft cloth, but the support must be easy to remove if vomiting occurs. Do not apply a tight bandage around the head and jaw.

A wrapped cold pack placed on the outside of the face may reduce swelling. Do not place ice directly on the skin. Avoid food and drink while waiting for urgent assessment because sedation, anesthesia, or a procedure may be needed. Follow emergency-service instructions if care will be delayed or the person has another condition that affects fasting.

Treatment of a fracture depends on its location, whether it is displaced, the condition of the teeth, and whether the bone is exposed to the mouth or outside environment.

Some stable fractures can heal with pain control, close follow-up, and a soft or non-chew diet. Other fractures need reduction, meaning the bone is returned to proper alignment. The jaw may then be stabilized with plates and screws placed during surgery. In selected cases, the upper and lower jaws are temporarily held together with wires, elastic bands, or other devices so the bite remains aligned.

When the jaws are held together, the treatment team provides instructions about nutrition, oral hygiene, and what to do if vomiting or breathing difficulty occurs. Devices should not be cut or removed unless the treating team has explained when and how this should be done.

Cuts and damaged teeth may require separate treatment. Clinicians may review tetanus protection when there is an open wound. Antibiotics like amoxicillin or doxycycline may be used for certain open or contaminated fractures, but they are not automatically needed for every jaw injury.

A dislocated jaw is treated by returning the joint to its normal position. This is called reduction. A trained clinician uses controlled pressure while protecting their fingers from an involuntary bite. Pain medicine, local anesthetic, muscle-relaxing medicine, or sedation may be used depending on the situation. Do not attempt this maneuver at home, as incorrect pressure can cause a fracture or other injury.

After reduction, the clinician checks whether the teeth meet normally and whether the joint remains in place. A temporary supportive wrap may be used. Recovery instructions often include soft foods, avoiding very wide mouth opening, and supporting the chin during yawning.

People with repeated dislocations may be referred to an oral and maxillofacial surgeon or another TMJ specialist. Management can include exercises, changes in jaw habits, temporary support, injections, or surgery. The best option depends on why the joint is unstable and how often dislocation occurs.

Breathing problems and major bleeding are the most immediate concerns after severe facial trauma. Blood, broken teeth, swelling, or loss of normal jaw support can interfere with the airway.

Later complications of a fracture may include infection, poor bone healing, or healing in the wrong position. If alignment changes, the teeth may not meet correctly. This is called malocclusion. Some people develop lasting numbness of the lip or chin if a nerve was bruised or damaged.

Other possible problems include tooth loss, difficulty chewing, reduced jaw movement, persistent pain, or TMJ symptoms. Poor food intake during recovery can lead to weight loss or dehydration if nutrition is not planned carefully.

A dislocated jaw can dislocate again, especially if it has happened before. Delayed treatment may allow muscle spasm and swelling to increase, making reduction more difficult. Most people recover well when the injury is recognized, treated, and followed appropriately.

Keep all scheduled appointments with the surgical, dental, or trauma team. Follow-up visits allow the clinician to check the bite, wound healing, joint movement, nerve sensation, and any plates, screws, wires, or elastic bands.

Use the recommended food texture for the full period advised by the treating team. Soft or non-chew meals may need to provide extra protein and calories. A dietitian can help when eating is difficult or recovery will be prolonged.

Oral hygiene is important because food and bacteria can collect around wounds and fixation devices. Follow the care team’s instructions for brushing, rinsing, and cleaning around wires or plates. Avoid activities that could cause another blow to the face until the clinician confirms that healing is adequate.

Contact the treating team promptly for increasing pain or swelling, fever, pus or a bad taste from a wound, worsening numbness, new difficulty opening the mouth, loose fixation, or a bite that is becoming less aligned. These concerns need timely assessment but are not always emergencies.

Seek emergency help for trouble breathing, choking, uncontrolled bleeding, fainting, severe confusion, or rapidly increasing swelling. A jaw that dislocates again and becomes stuck should receive urgent medical care; do not try to force it back into place.