Pano

Question 1

Panoramic Radiography

Answer 1

external technique used to examine upper and lower jaw on a single film. film + tubehead rotate at set vertical angulation, images combine into one

Question 2

Pano: Purpose

Answer 2

supplements btwgs/pa’s, evaluates dentition + structures, impacted teeth, eruption patterns during growth, detects conditions/lesions/diseases/trauma - NOT a substitute for intraoral films (detecting caries)

Question 3

Rotational Center

Answer 3

receptor and tube head rotate around this pivotal axis point

Question 4

Focal Trough

Answer 4

3d curved zone around dental arches, set to accommodate the average jaw

Question 5

Image Receptors

Answer 5

digital or PSP plate (photo-stimuable phosphor), extraoral screen film (light sensitive) - film is placed between intensifying screens

Question 6

Intensifying Screens

Answer 6

calcuim tungstate (blue light), rare earth (green light, faster, less radiation)

Question 7

Midsagittal Plane

Answer 7

divides into right / left

Question 8

Frankfort Plane

Answer 8

passed through floor of orbit (eye) + external auditory meatus

Question 9

Anatomic Features present in pano

Answer 9

anterior teeth with pulp, posterior teeth similar in size on both sides, both condyles, palate above max. apices, ramus width same both sides

Question 10

Overexposed Pano =

Answer 10

dark

Question 11

Underexposed Pano =

Answer 11

light

Question 12

Ghost Images

Answer 12

metal/dense artifacts to be removed! jewelry, glasses, hearing aids, etc. ; appear larger/higher on opposite side

Question 13

Pano Errors

Answer 13

lead apron w/ thyroid collar, lip/tongue position, chin up, chin down, too anterior, too posterior, head turned slumped posture

Question 14

Pano Error: Lip/Tongue position

Answer 14

lips should be closed on bite block; tongue should be against palate - errors can cause radiolucent shadows

Question 15

Pano Error: Chin up

Answer 15

chin too high = reverse smile line :( - make frankfort plane parallel

Question 16

Pano Error: Chin down

Answer 16

chin too low = exaggerated smile line :) - make frankfort plane parallel

Question 17

Pano Error: Anterior

Answer 17

teeth too far forward on bite block; appear skinny/out of focus - position anterior teeth in end-to-end relationship

Question 18

Pano Error: Posterior

Answer 18

teeth too far back on bite block; appear fat/out of focus. -position anterior teeth in end-to-end relationship

Question 19

Pano Error: Head turned

Answer 19

ramus + posteriors appear unequal (further side magnified), - make sure midsagittal plane perpendicular w/ floor

Question 20

Pano Error: Slumped Posture

Answer 20

spine can appear in image, have patient sit tall and straight

Question 21

Pano: Advantages

Answer 21

field size, simplicity, patient cooperation, minimal exposure

Question 22

Pano: Disadvantages

Answer 22

image quality, focal trough limitations, distortion, equipment cost