Digital Panoramic dental X-ray and Cephalometry

Digital cephalometry

This is an X-ray taken of the side of your face with very precise positioning so that various measurements can be made to determine the current and future relationship of your mandible (jaw) to your maxilla (cheek bone) and therefore the nature of your bite. This helps the dentist to plan any orthodontic treatment if it is necessary. Cephalometry is used to obtain measurements of the structures of the lower face.

What is the test used for?
These are special x-ray techniques which look at the teeth and jaw.
An OPG ("orthopantogram") gives a panoramic view of the mouth, giving information on the teeth and the bones of the upper and lower jaw. Cephalometry is used to obtain measurements of the structures of the lower face.

What is the preparation for the test?
For some cephalograms, some dentists and oral surgeons like us to "paint" a stripe of barium paste on your face to allow them to measure more accurately. Otherwise, no preparation is necessary.

Will I have to undress?
You will not have to undress, but will be asked to remove any removable jewellery in the region of your face and head. Metal will cause artifacts on the x-rays, and may obscure abnormalities.

Where will I be for the test?
The dental x-ray machines are specialized pieces of equipment kept in our general x-ray room. You will be asked to stand with your face resting on a small shelf to provide accurate positioning. For an OPG, you will be asked to bite gently on a sterile mouth piece to steady your head. The radiographer will guide you through it all, and the examination is almost never uncomfortable.

How is the test done?
An OPG aims to view the jaw, while blurring out the other structures of the face and skull. This is done using a technique called "tomography". As the X-ray tube moves around your head, the x-ray film moves in the opposite direction behind your head. This generates an image where the jaw is in focus, and the skull is blurred.

Cephalograms are taken in one or both of two planes: anterior, where the face is viewed straight on, and lateral, where the face is viewed from the side.

Does it hurt?
No.

How long will it all take?
5 to 15 minutes depending on the number of views required.

And after the test?
You can go home. If you have to take the films and report with you, you might wait for about 20 minutes to allow for film processing, interpretation by the radiologist and typing.

For all known X-ray procedures with and without contrast. If there is a chance the parent (mother) is pregnant, we ask her not to attend in the exam room, even when wearing a lead apron. If there the patient is pregnant, she should inform us before the exam, so that the radiol­ogist can contact her doctor, and ask about possibility of performing the examination.

Digital computerized panorama

• Gives higher contrast resolution for images
• Panorama or an OPG (“orthopantogram”) gives a panoramic view of the mouth, giving information on the teeth and the bones of the upper and lower jaw
• Demonstrates number, position and growth of all your teeth including those that have not yet surfaced
• Can obtain full improved panoramic views of maxillary and mandibular regions
• Open-closed mouth TMJ
• Posterior-anterior TMJ

So what is an Orthopantomogram?
An Orthopantomogram, or OPG, is a special type of x-ray looking at the lower face that displays both the upper and lower teeth in a long flat line.

OPG and Lateral Cephalometry
It demonstrates the number, position and growth of all your teeth including those that have not yet surfaced. You also may have been requested by your dentist to have a cephalogram. This is an x-ray taken of the side of your face with very precise positioning so that various measurements can be made to determine the current and future relationship of your mandible (jaw) to your maxilla (cheek bone) and therefore the nature of your bite. This helps the dentist to plan any orthodontic treatment if it is necessary.

Examination
The films are taken by a radiographer (technologist trained in medical imaging) and interpreted later by a radiologist (a specialist doctor trained to read medical images). The procedure is brief (about 15 minutes), painless and simple, but it
is vital that you keep completely still once the radiographer has carefully positioned you.

Procedure
During the OPG an arm of the machine will rotate around your head but it will not come into contact with you. The radiographer will tell you to bite on a small plastic mouthpiece attached to the OPG machine, which keeps the top and bottom rows of teeth separated. Occasionally a film may need to be repeated if there is any movement, or if the position is not exact.

You have the option to either wait for your films or alternatively you may wish to come back and collect them at a more convenient time.