Orthopantomogram (OPG) at Chichester Hospital

What is an orthopantomogram (OPG)?

An orthopantomogram (OPG), also called a panoramic X-ray, is a dental X-ray that captures a single, wide image of your entire mouth, including all your teeth, both jaws, your sinuses, and your jaw joints (the temporomandibular joints, or TMJ). Unlike a standard dental X-ray, which focuses on just one or two teeth, an OPG shows the whole picture in one go.

Why might I need one?

Your dentist, orthodontist, oral surgeon or another specialist might request an OPG to:

• assess the alignment of your teeth and jaw, or plan orthodontic treatment
• identify impacted teeth, particularly wisdom teeth
• detect jawbone problems, such as cysts, tumours, infections or bone loss
• plan for dental implants, extractions, or complex root canal treatment
• investigate jaw pain, clicking, or suspected TMJ problems
• look into ongoing pain that hasn't been explained by other means
• monitor how a child's teeth and jaw are developing, including teeth that haven't yet come through.

An OPG is only carried out following a referral from a healthcare professional, and only when there's a genuine clinical need for it.

What are the benefits of having it?

An OPG gives a comprehensive, wide view of your entire mouth in a single image, rather than needing several separate X-rays to build up the same picture. It's quick, comfortable and non-invasive, with no need for anaesthetic or injections, and it generally involves less radiation than a full set of individual dental X-rays covering the same area.

Are there different types of the test?

An OPG is a single, standardised type of X-ray, so there aren't different versions of the test itself. However, your dentist might occasionally recommend a related but different scan called a CBCT (cone beam CT), which gives a more detailed, 3D image rather than a flat 2D one. This is usually reserved for more complex cases, such as detailed implant planning, since it involves a higher radiation dose than a standard OPG.

How do I prepare for the test?

No special preparation is needed for an OPG. You'll be asked to remove any jewellery, glasses, or other metal objects from around your head and neck beforehand, since these can interfere with the image.

Tell your dentist or the clinic if you are, or might be, pregnant, as this can affect whether the scan is suitable for you.

What happens during the test?

1. You'll stand, or sometimes sit, in the machine, with your chin resting on a support and your hands gently holding the handles.
2. You may be asked to bite gently on a small mouthpiece to help keep your head steady.
3. The machine's arm rotates around your head, taking the X-ray images from different angles as it moves.
4. You'll need to stay completely still throughout, though the scan itself is quick.
5. Once it's finished, you can go straight back to your normal activities.

Sources give slightly different timings, but the scan itself usually takes from around 30 seconds up to about a minute.

What happens after the test?

You can return to your normal activities straight away, since there's no discomfort or recovery time involved. Your dentist or specialist will review the images, and if you were referred elsewhere for the scan, the images are usually sent back to them so they can discuss the results and next steps with you at your regular appointment.

What are the risks or side effects?

An OPG involves a very low dose of radiation and is considered safe. It's non-invasive, with no injections or anaesthetic, and doesn't cause any physical discomfort.

OPGs are only carried out when clinically justified, following UK radiation safety standards. They aren't routinely recommended during pregnancy unless there's a specific clinical need, so it's important to tell your dentist if you are, or think you might be, pregnant.