Chapter 17

Question 2

What happens if the arches are positioned too far back in the focal trough?

Answer 2

The anterior teeth will appear blurred and magnified.

Question 3

What happens if the arches are positioned too far forward in the focal trough?

Answer 3

The anterior teeth will appear blurred and diminished in width.

Question 4

What is the likely cause of a reversed smile (frown) in a panoramic image?

Answer 4

The patient’s chin was positioned too high.

Question 5

What corrective action can avoid an image that mimics caries of the anterior teeth?

Answer 5

Have the patient close his or her lips on the biteblock.

Question 6

Which statement about extraoral film is incorrect?

Answer 6

Film should slide across the intensifying screens when placing it in the cassette.

Question 7

What is true regarding intensifying screens?

Answer 7

The thicker the emulsion, the faster the speed of the screen.

Question 8

Is a panoramic radiograph often selected to identify caries?

Answer 8

FALSE

Question 9

Is panoramic radiography based on the principles of tomography?

Answer 9

TRUE

Question 10

Do most panoramic machines have wide focal troughs in the anterior region?

Answer 10

FALSE

Question 11

Is the biteblock used to position the arches correctly in the focal trough?

Answer 11

TRUE

Question 12

If the patient’s head is rotated to the right, do the teeth on the right appear magnified?

Answer 12

FALSE

Question 13

If the patient’s chin is tipped up, does the image appear as an exaggerated smile?

Answer 13

FALSE

Question 14

Will a frown appearance to the arches result when the patient’s chin is positioned too high?

Answer 14

TRUE

Question 15

Will jewelry in the head and neck area produce artifacts on the panoramic image?

Answer 15

TRUE

Question 16

Should the patient rest the tongue against the palate during exposure?

Answer 16

TRUE

Question 17

Must careful loading of a flexible plastic sleeve cassette ensure that the film is completely seated?

Answer 17

TRUE

Question 18

Is it necessary to use intensifying screens in film-based radiography?

Answer 18

TRUE

Question 19

Do calcium tungstate or barium strontium sulfate emit green light when they absorb x-rays?

Answer 19

FALSE

Question 20

Is the technique used to show detailed images of structures called tomography?

Answer 20

TRUE

Question 21

Does the panoramic technique require more operator time than a full mouth series?

Answer 21

FALSE

Question 22

Must the radiographer be skilled at setting the correct size of the focal trough?

Answer 22

FALSE

Question 23

Do side positioner guides assist in locating the correct lateral dimension?

Answer 23

TRUE

Question 24

Does the x-ray tube head move around the back of the patient?

Answer 24

TRUE

Question 25

Do all panoramic images have between 10 and 30 percent image magnification?

Answer 25

TRUE

Question 26

Is the focal trough of all panoramic radiographic machines three dimensional?

Answer 26

TRUE

Question 27

What happens to the image if intensifying screens and film are not in tight contact?

Answer 27

The resultant image is blurry.

Question 28

What type of gloves are required when handling extraoral film in the darkroom?

Answer 28

None.

Question 29

How many intensifying screens are inside a cassette?

Answer 29

Two.

Question 30

What is the front cover of a rigid extraoral film cassette constructed from?

Answer 30

Plastic.

Question 31

What is the back cover of a rigid extraoral film cassette constructed from?

Answer 31

Metal.

Question 32

Why should cassettes and intensifying screens be examined prior to use?

Answer 32

To check for light tightness and cleanliness.

Question 33

What types of digital image receptors are available for panoramic imaging?

Answer 33

CCD and CMOS-APS solid-state sensors and PSP imaging plates.

Question 34

Do extraoral films have an embossed identification dot?

Answer 34

No.

Question 35

What are the steps for processing a PSP plate panoramic image?

Answer 35

The PSP plate is scanned to convert analog data into digital information.

Question 36

What is the purpose of the head positioner guides when exposing panoramic images?

Answer 36

To position the patient correctly.