Extra-Oral Radiography

Question 1

What are the Extra-Oral views?

Answer 1

Images relating to mandible

• Postero-Anterior Mandible
• Lateral oblique of mandible
• DPT

Images relating to maxilla and cranium

• Lateral Cephalogram(skull)
• Occipito-mental views (0,10 & 30 degrees ) (face)
• Sailography

Question 2

What does this terminology stand for?:

PA, AP, OM, Lateral

Answer 2

• PA - Postero-anterior
• AP - Antero-posterior
• OM - Occipito-mental

Lateral

The above relate to the direction of the x-ray beam

Question 3

What is Scatter Radiation?

Answer 3

When x-rays pass through tissues, some are scattered -Compton scattering

in skull radiography, increase in the field of the beam - more scatter produced

this adds to the background fog-

greyer film- lacking contrast

Question 4

What is a Anti-scatter grid?

Answer 4

To stop photons scattered in patient reaching the film.

Avoids degrading image & reducing contrast.

Narrow strips of lead alternating with plastic.

Fixed/stationary or moving/oscillating

Question 5

Lateral oblique mandible

Answer 5

Question 6

Answer 6

Question 7

Answer 7