Broken jaw

The jawbone is made up of the upper (maxilla) and lower (mandible) jawbone. A break may occur in either or both of these bones.

Common causes

A fall such as from a bicycle or motorcycle
Dashboard impact during a car collision
A fall or collision during contact sports
A punch to the jaw

Common signs and symptoms

Bruising, swelling and tenderness along the jaw or below the ear
The feeling that the teeth don’t fit together properly
Missing or loose teeth
Swelling or black and blue discolouration of the gum over the jawbone, or under the tongue
Difficulty opening the mouth
Pain in the jaw joint
Numbness in the lower lip or chin
Shifting of the lower jaw on opening the mouth

Treatment for a jaw fracture:

If the fracture is minor, no treatment may be required other than pain medication for discomfort and a soft diet for three weeks to minimize pain while chewing.

However, if the fracture is more serious, surgical treatment is often required to align and immobilize the bone so that it can heal properly.

Jaw wiring is the usual surgical choice for moderate to severe fractures. A wire is used to hold the jaw in place and to keep it from moving. This will help the bones heal properly.
Some fractures will require placement of screws and plates in the bone.

In general, once an uncomplicated jaw fracture is treated, healing usually takes one to two months.

What happens if the teeth are mobile, displaced or fractured?

If the teeth and/or the surrounding tissue were traumatized, the dentist will be called to assess and treat your child’s teeth.

If your child’s tooth is broken, keep the broken piece and go to an emergency department or to a dentist immediately. The dentist will glue it back in place.
If the tooth is displaced, replace it in its original position. If this is not possible, place the tooth in cold milk and go to an emergency department or to a dentist immediately.

Can complications occur following a jaw fracture?

In most cases, the prognosis is very good, especially when the fracture is treated promptly and properly. If a tooth is in the line of the fracture, however, it may prevent good healing

In rare cases when the fracture is ignored or healing is poor, long-term complications may include:

Facial deformity
Chronic facial pain
Limitation of movement of the jaw joint and malocclusion (abnormality in the coming together of teeth)

How to prevent a jaw injury:

You can help prevent jaw fractures by avoiding trauma to the chin and lower face.

Always use the proper child seat when your child is in a car. It will help protect the facial bones and upper body from impact. Other types of trauma, like traumatic brain injuries, can also be prevented.
Your child should always wear well-fitted headgear and a mouth guard during contact sports. In addition to protecting the teeth from impact, mouth guards offer some protection against jaw fractures.

Reviewed by Trauma specialists at the Montreal Children’s Hospital.
Last updated: March 2020