Jaw (Mandible) X-ray (complete)

What it is

The lower jaw is one continuous bone running from the joint in front of one ear, down and around the chin, and back up to the joint in front of the other. Because it is a closed arch hinged at both ends, a force hard enough to break it in one place frequently breaks or dislocates it somewhere else too. A complete series therefore images the whole bone: the body along each side, the upward branches behind the molars, the chin at the front, and the two joints. Each view is angled to project one segment clear of the skull behind it. The radiologist reads them together, following the smooth outline of the bone and the line of the teeth for any step or break.

Why it is done

• To look for a fracture of the lower jaw after a blow, a fall or a collision, along the whole arch rather than just where it hurts
• To assess a jaw that has come out of its joint or will not close properly, where the teeth no longer meet as they should
• To look at bone around the roots of the teeth and at the jaw joints
• To investigate swelling, a cyst or another lesion in the jaw bone
• To check the position of bone and hardware after jaw surgery

What to expect

Earrings, necklaces, piercings, hairpins and removable dentures or retainers all come off, since anything metal sits directly over the bone being examined. You sit or lie with your head against the image plate and the technologist turns and tilts your head between views — cheek to the plate at one angle, then the other side, then chin up for a view of the whole arch. Some views ask you to hold your mouth open. Each exposure needs a second or two of stillness. Moving a broken jaw is painful; say so, and the positioning can be adjusted. The series usually takes ten to fifteen minutes. A panoramic dental image or a CT is sometimes used instead, depending on what is being looked for.

Questions worth asking

• Would a panoramic dental image or a facial CT answer this instead, and how do the prices compare at this facility?
• If this is jaw-related, will it be processed under medical insurance or dental insurance? That decision can change what you owe more than the price does.
• Is the full multi-view series covered by the quoted price, or is it quoted per view?
• If a fracture is found, is the oral or maxillofacial surgeon's assessment part of today's visit or a separate consultation charge?