An examination of the mouth can only assess the visible side of a tooth. For the spaces between the teeth, the roots and the bone, an X-ray is needed.
Why are dental X-rays taken?
- To detect decay that starts between two teeth and cannot be seen
- To see decay under old fillings and crowns
- To identify infection, abscesses and cysts at the root tip
- To assess the position of impacted teeth and wisdom teeth
- To measure the level of bone loss in gum disease
- To plan implants, root canal treatment, orthodontics and surgery
- In children, to follow erupting and unerupted teeth and jaw development
Types of X-ray
Periapical X-ray
A small film that shows one or a few teeth in detail right down to the root tip. Used in root canal treatment and for complaints about a single tooth.
Bitewing X-ray
Shows the surfaces where the back teeth touch each other. It is the most reliable way to catch decay between the teeth early.
Panoramic X-ray
Shows all the teeth, the upper and lower jaws and the jaw joints on a single film. Requested at a first examination to assess the overall picture, see impacted teeth and plan treatment.
Three-dimensional imaging (dental tomography)
May be requested by the dentist when the three-dimensional structure of the bone needs to be seen, for example in implant planning or for impacted teeth close to a nerve.
How is an X-ray taken?
- PreparationEarrings, necklaces, hair clips, glasses and removable dentures in the head and neck area are taken off.
- ProtectionA lead apron and thyroid collar are used where necessary.
- Taking the imageFor a periapical film a small sensor is placed in the mouth. For a panoramic film you stand while the machine rotates around your head. It takes a few seconds and is painless.
- AssessmentYour dentist examines the image and explains the findings to you on the screen.
Are dental X-rays harmful?
The radiation dose used in dental X-rays is very low. Digital systems have reduced it further; the dose of a single small dental film is comparable to a few hours to a day of the natural background radiation we receive in daily life. Even so, X-rays are only requested when they are necessary and will help the diagnosis.
If you are pregnant or might be, be sure to say so before the X-ray. Non-urgent X-rays are postponed until after the birth; where necessary they can be taken with protective measures.
Frequently asked questions
Does an X-ray have to be taken at every examination?
No. How often X-rays are taken depends on the person's risk of decay, age and complaint. One may be requested at a first examination for a general assessment; at later check-ups it is repeated only if needed.
Are dental X-rays taken for children?
Yes, when necessary. For children the dose is adjusted to age and weight and a protective apron is used. Decay between the teeth and erupting teeth can often only be seen on an X-ray.
How long does a panoramic X-ray take?
The exposure itself takes about 10 to 20 seconds. With preparation it is finished in a few minutes.
Can I bring an X-ray I had taken before?
Yes. If you have a recent X-ray of good quality, bring it with you; your dentist will decide whether a new one is needed.
This page is for general information and is not a substitute for an examination. The right treatment for you is decided after your dentist's examination and any imaging needed.