Fractures of the Jaw and Midface
Injuries to the face often occur in combination. For example, the eye and the nose or the mouth and the cheek can be damaged as a result of the same injury.
A broken lower jaw usually causes pain and swelling, changes the way the teeth fit together, and prevents the person from fully opening the mouth.
Fractures of the middle part of the face can cause swelling, double vision, facial numbness, a sunken eyeball, changes in the way the teeth fit together, and/or inability to fully open the mouth.
A lower jaw fracture is treated by resting the jaw, surgery, or wiring the jaw closed until bones heal.
A midface fracture can be treated surgically, but surgery usually is done only if the fracture causes problems other than pain and swelling, such as facial deformity.
The term jaw fracture often refers to a break of the lower jaw (mandible). Fractures of the upper jaw (part of the bone called the maxilla) are sometimes called jaw fractures but are usually considered facial fractures.
The mandible is most often broken as a result of blunt trauma, such as being punched or hit with a baseball bat or other object.
Fractures of the maxilla can occur when the front of the face smashes against an immovable object, as occurs in a fall from a height or a motor vehicle crash. Some are caused by being hit by a blunt object such as a fist or weapon. Some jaw fractures break only a tooth socket.
Fractures of the Midface
Many fractures of the face, usually ones that result from a substantial amount of force (such as a motor vehicle crash), fall into one of the following categories (called the LeFort classification):
A fractured mandible usually causes pain and swelling of the jaw, and people often feel that their teeth do not fit together as they should. Often, the mouth cannot be opened wide, or it shifts to one side when opening or closing.
Fractures of the maxilla often cause swelling and deformity of the face. Swelling rarely becomes severe enough to block the airway and interfere with breathing. However, any injury forceful enough to fracture the maxilla may also injure the spine in the neck (see Injuries of the Spinal Cord and Vertebrae) or cause a brain injury.
Other symptoms depend on where the fracture is located.
Fractures of the bones of the floor of the eye socket may cause double vision (because the muscles of the eye attach nearby), numbness in the skin below the eye (because of injuries to nerves), or a sunken eyeball.
Fractures of the cheekbone (zygomatic arch) can cause inability to fully open the jaw, a change in the way the teeth fit together, and an irregularity in the cheekbone that can be felt when running a finger along it.
Other fractures of the maxilla that extend down into the jaw can cause inability to fully open the jaw and a change in the way the teeth fit together.
Fractures that extend through a tooth or its socket create an opening into the mouth that can allow bacteria in the mouth to infect the mandible or maxilla.
A doctor's examination can usually determine if the jaw is broken. Usually x-rays are taken to diagnose fractures of the mandible or only a tooth socket. Computed tomography (CT) is done to diagnose fractures of the maxilla. Neck x-rays are often taken to rule out spinal damage. If a person has symptoms of brain injury, CT of the brain is done. If the person has vision problems or an injury near the eye, an eye examination is done.
If people suspect their jaw is fractured, they should go to the emergency department immediately.
If swelling or bleeding begins to close the breathing passages, doctors may need to insert a tube (endotracheal tube) to help the person breathe.
Treatment of mandible fractures involves resting the jaw so that the bone can heal. Mild fractures may require only that the person not chew, so doctors prescribe a liquid or soft-food diet. More severe fractures (such as those with breaks in more than one place or those in which the ends of the bone are separated, called a displaced fracture) require that the jaw be repaired.
Doctors may screw metal plates into the bone on each side of the fracture, or they may wire the person's upper and lower jaws together for several weeks. If the jaw is wired shut, the person is only able to drink liquids through a straw. Because only part of the tooth surface can be brushed while the jaw is wired shut, doctors prescribe a mouth rinse to be used twice daily. After several weeks of being wired shut, the jaw usually needs to be strengthened with exercises.
In children, some mandible fractures near the ear are not immobilized. Instead, mild restriction of jaw motion with a device for 5 to 10 days is enough.
Maxillary fractures are treated with surgery if they cause problems such as vision symptoms, a change in the way the teeth fit together, limitation of jaw opening, a sunken eyeball, facial numbness, or an unacceptable change in appearance. Doctors often wait a few days after the injury (when swelling subsides) to decide whether surgery is needed. Surgery typically involves fixation with screws and plates. After surgery, the jaws may need to be immobilized but often for only a few days, after which people should eat only soft foods for several weeks.