AP open mouth cervical

Question 1

What SID is recommended?

Answer 1

30”, increases view of odontoid process

Question 2

What imaginary line should be aligned perpendicular to the IR for this image?

Answer 2

Occlusional plane

Question 3

What is the central ray location?

Answer 3

Midpoint of open mouth

Question 4

Why is it recommended that the patient say “ah” during exposure?

Answer 4

So patient can open mouth as wide as possible

Question 5

What is best demonstrated in this image?

Answer 5

c1 and c2 should be seen, upper teeth, base of odontoid process

Question 6

If the occipital bone is superimposed over the dens, what positioning error occurred?

Answer 6

Head extended too far back

Question 7

If the upper teeth are superimposed over the dens, what positioning error occurred?

Answer 7

Chin down too far

Question 8

If the dens cannot be obtained without superimposition, what additional view can be taken?

Question 9

How to determine rotation?

Answer 9

If left rami moves away from spine, rotation to left. Rami should be symmetrical