Deck 4: Factors Affecting Radiographic Quality

Question 1

Which of these statements is FALSE?

A) Structures should be magnified to enhance interpretation.
B) An area of interest must be recorded completely with sufficient surrounding structures for a frame of reference.
C) A radiograph should be of proper density, contrast, and definition.
D) An image should be free of errors.

Answer 1

Structures should be magnified to enhance interpretation.

Question 2

Which of the following indicates a radiographic image that is black and white with few shades of gray in between?

A) Short resolution
B) Long resolution
C) Short scale
D) Long scale

Answer 2

Short scale

Question 3

An original radiograph is exposed at 8 mA for 1.0 seconds. If the mA is increased to 10, which of the following exposure times would be correct to maintain radiographic density?

A) 0.4
B) 0.6
C) 0.8
D) 1.0

Answer 3

0.8

Question 4

Each of the following results in image unsharpness EXCEPT one. Which one is the EXCEPTION?

A) Patient movement during exposure
B) Image receptor positioned close to the teeth
C) A short PID
D) The use of intensifying screens

Question 5

Each of the following is a term used to describe visual image characteristics EXCEPT one. Which one is the EXCEPTION?

A) Sharpness
B) Contrast
C) Milliamperage
D) Density

Question 6

A radiographic film with a small crystal size

A) creates sharpness.
B) causes magnification.
C) decreases exposure time.
D) increases contrast.

Question 7

Which of these is NOT a shadow-casting principle?

A) A large focal spot
B) Long target-image receptor distance
C) Short object-image receptor distance
D) Parallel object-image receptor relationship

Question 8

Which of these statements regarding radiographic contrast is FALSE?

A) There are few shades of gray in a radiograph with short-scale contrast.
B) Short-scale contrast describes a radiograph in which the density differences between adjacent areas are large.
C) There are many shades of gray in a radiograph with long-scale contrast.
D) Long-scale contrast describes a radiograph in which the density differences between adjacent areas are large.

Question 9

Which of the following is recommended for increasing radiographic contrast while maintaining radiographic density?

A) Increase kVp and increase exposure time.
B) Decrease kVp and decrease exposure time.
C) Increase kVp and decrease exposure time.
D) Decrease kVp and increase exposure time.

Question 10

Image magnification can be decreased by:

A) increasing the target-object distance.
B) increasing the object-image receptor distance.
C) decreasing the target-surface distance.
D) increasing the focal spot size.

Question 11

Which of the following statements about dental radiographic exposure variables is true?

A) Increasing the mA darkens the radiograph.
B) Decreasing exposure time darkens the radiograph.
C) Exposure time is difficult to change on most machines.
D) Milliamperage affects radiographic contrast.

Question 12

Which of the following refers to a radiographic image that is black and white with many shades of gray in between?

A) Low contrast
B) High contrast
C) Low density
D) High density

Question 13

When changing the PID length from 8 inches (20.5 cm) to 16 inches (41 cm), what corresponding change must be made to maintain image density?

A) Decrease exposure time.
B) Increase exposure time.
C) Decrease kilovoltage.
D) Increase kilovoltage.

Question 14

The inverse square law states that the intensity of the radiation:

A) increases as the distance from its source increases because the beam of radiation converges.
B) decreases as the distance away from its source increases because the beam of radiation diverges.
C) increases as the distance away from its source increases because the beam of radiation diverges.
D) decreases as the distance away from its source increases because the beam of radiation converges.

Question 15

Which kVp setting produces long-scale image contrast?

A) 65 kVp
B) 75 kVp
C) 85 kVp
D) 95 kVp

Question 16

The difference in densities between adjacent areas on the radiograph is termed:

A) sharpness.
B) density.
C) resolution.
D) contrast.

Question 17

Which of these statements is FALSE?

A) Increasing the target-image receptor distance reduces penumbra.
B) Radiation intensity is directly proportional to the square of the distance from the source.
C) A long PID increases image sharpness.
D) A recessed tube increases the target-image receptor distance.

Question 18

Radiolucent images appear dark or black because:

A) hard radiation was allowed to reach the image receptor.
B) dense structures stopped x-rays from reaching the image receptor.
C) soft radiation was stopped before reaching the image receptor.
D) less dense structures permitted more x-rays to reach the image receptor.

Question 19

The degree of overall blackness of a radiographic image is termed:

A) sharpness.
B) density.
C) resolution.
D) contrast.

Question 20

Each of the following appear radiopaque EXCEPT one. Which one is the EXCEPTION?

A) Bone
B) Dentin
C) Pulp
D) Enamel

Question 21

Radiographic density (film darkening) is decreased when the milliamperage or exposure time is increased.

Question 22

The term "short-scale contrast" describes a radiograph in which density differences between adjacent areas are small.

Question 23

That portion of the radiographic image that appears light is called "radiolucent."

Question 24

Theoretically, the ideal focal spot would be a point source.

Question 25

Only one film should be placed in contact with the intensifying screens used for extraoral radiography.

Question 26

Grids absorb scattered x-rays.

Question 27

Slight movement of the tube head during exposure of a radiograph effectively increases the size of the focal spot on the target within the tube head.

Question 28

Thicker intensifying screens increase the sharpness of extraoral radiographs.

Question 29

A small focal spot reduces penumbra.

Question 30

White areas on a radiographic image are termed radiolucent.

Question 31

Some clinicians prefer a radiographic image that is of low contrast, and others prefer a radiographic image that is of high contrast.

Question 32

Sharpness/definition refers to the detail and clarity of the structures on a radiograph.

Question 33

Radiographic image unsharpness is generally caused by movement of the patient, image receptor, or tube head during exposure.

Question 34

The film should be in close physical contact with the intensifying screens.

Question 35

Digital imaging sharpness can be affected by pixel size and distribution.

Question 36

The target-object distance is the distance between the focal spot on the target and the skin surface of the patient.

Question 37

The target-image receptor distance should be short to create radiographs with the best definition.

Question 38

Penumbra is a device used in extraoral radiography to prevent scatter radiation from fogging the image receptor.

Question 39

A radiographic image with many shades of gray is said to have low contrast.

Question 40

Increasing the kVP results in a more penetrating x-ray beam.

Question 41

What is radiographic density?

Question 42

What is long-scale contrast?

Question 43

What is penumbra?

Question 44

What types of tissues or structures appear radiopaque on radiographs?

Question 45

The quality of the beam of radiation is determined by which exposure factor?

Question 46

What types of tissues or structures appear radiolucent on radiographs?

Question 47

Why should the x-ray film be placed parallel to the long axis of the tooth?

Question 48

What is the relationship between kVp and contrast?

Question 49

What is short-scale contrast?

Question 50

What is radiographic contrast?