Radiology 5

1. Intraoral film packets must be

Resistant to salivary seepage

Flexible

Light tihgt

Easy to open in the darkroom

All of the above

2. Radiographs should always be viewed

In a well lit room

On a viewbox

In the operatory

By holding them up to a celling light

Using hight from a window

3. Intraoral film packets must be

Resistant to salivary seepage

Flexible

Light tight

Easy to open in the darkroom

All of the above

4. The advantage of a film that has emulsion on both sides is that

The film requires less radiation exposure

The image produced is less distorted

The film has less sensitivity to radiation

Processing solutions work better

The film is easier to mount

5. Which of the following materials is most resistant to x radiation?

Copper

Molybdenum

Tungsten

Lead

Aluminum

6. What is the major advantage in using the fastest speed film and high kilovolt peak?

It increases film density

It increases film contrast

It produces a clearer image

It reduces the radiation exposure to the patient

It makes film easier and faster to develop

7. The ALARA principles refers to

Obtaining informed consent

The disinfection procedures recommended in dental radiography

Obtaining diagnostically acceptable radiographs with minimal exposure to radiation

Decreasing the processing time for exposed radiographs

None of above

8. Which of the following film sizes is considered to be standard adult film?

Size#0

Size#1

Size#2

Size#3

Size#4

9. Which form of radiation can cause ionization of atoms?

Radar

Microwaves

Radio waves

Visible light

Gamma rays

10. The difference in degrees of blackness on a radiograph is called

Density

Tone

Contrast

Fogging

Shades

11. Film fog occurs when all or part of a radiograph is darkened by

An imbalance or exhaustion of processing solutions

A light leak

Improper safelighting

Improper safelilghting

All of the above are potential sources

12. The device that converts x ray energy into visible light is called a(n)

Cassette holder

Step down transformer

Intensitying screen

Nonscreen film

Screen film

13. If the intensitying screens are not in perfect contact with the film which of the following will occur?

The screen may be damaged

The film may be damaged

There will be a light leak

There will be a loss of image sharpness

A thin film will result

14. The intensity of the beam is affected by the

Kilovolt peak

Milliamperage

Exposure time

Focal film distance

All of the above

15. Nonscreen film is routinely used in extraoral radiography

True

False

16. How many times per second is the polarity reversed in a dental xray machine operating on an alternating current?

30

15

60

45

17. For x ray timers calibrated in impulses how many impulses are there in a second?

10

30

60

120

15

18. To what does the term film speed refer?

The developing time needed

Sensitivity to x radiation

Half life

Degree of blackness on the exposed radiograph

Shelf life

19. The intensifying screen that emits blue light and must be used with film that is sensitive to blue light is a

Nonlight screen

Calcium tungstate screen

Rare tungstate screen

Rare earth screen

Phosphor calcium screem

20. A long FFD is desirable because

More radiation is absorbed by the tissues

The resulting radiation is more penetrating

More soft radiation strikes the object

The central rays of the primary beam are less divergent

Overexposure rarely occurs

21. Ionization has occurred when

Cell death occurs

Photons penetrate matter

Radiant energy is converted to heat

An electron is displaced from its orbit

None of the above

22. Under the new metric system for measuring dose SI the rem replaced by the

Rad

Gray

Sievert

Becquerel

Curie

23. In taking dental radiographs the greatest dose of radiation to structures in the patient jaw comes from

The primary beam

Leakage from the xray machine

Scatter from the patient face

Scatter from the pid

Secondary radiation

24. Which of the following travel at the greatest speed?

X ray

Gamma rays

Light

Microwaves

They all travel at the same speed

25. The advantage of a film that has emulsion on both sides is that

The film requires less radiation exposure

The image produced is less distorted

The film has less sensitivity to radiation

Processing solutions work better

The film is easier to mount

26. Which of the following statements cocerning background radiation is most accurate?

It gives us the maximum recommended dosage for radiation exposure

It can be avoided if an individual is cautious

It is found everywhere

It is only present in dental offices and medical facilities

None of the above are correct

27. The best way to clean the intensifying screens in extraoral cassettes is with

Detergent

Disinfectant solution

Cold sterillizing solution

Soapy water

A wire brush

28. Flexible cassettes are

Not used because of cracking of the emulsion

Are used in all panoramic units

Are used in some panoramic units

Are used for lateral oblique projections only

None of the above

29. Use of a kilovolt peak between 45 65 profuces

Scatter radiation

Fogging

A blurred image

An underexposed film

None of the above

30. Which of the following statement is false concerning film duplication?

The films to be duplicated are in close contact with the duplicating film.

The shiny side of the film is the nonemulsion side

If less film density is needed on the duplicate radiograph the exposure time is shortened.

The raised portion of the orientation dot faces toward the light source

The radiographs being duplicated should be removed from their respective mounts.

31. If the intensity of a beam of radiation is 12 at a point 12 inches from the target the intensity of the beam at 24 inches is

2

3

4

5

6

32. In 16 inch cylinder is used in the paralleling technique to

Reduce secondary radiation

Avoid magnification of the image

Avoid distortion of the image

Avoid superimposition of anatomic structures

Facilitate correct vertical angulation of the position indicating device pid

33. Which of the following types of scatter radiation occurs most often with dental x rays

Thompson

Compton

Photoelectric

Coherent

All of the above occur equally with dental x rays

34. In recent years the focus of prime concern from the effects of ionizing radiation used in dentistry has centered on

Somatic damage to the patient

Occupational exposure of dental workers

Genetic damage to patients

Cancer induction in patients

Its contribution to background radiation

35. X rays that are most likely to be absorbed by the skin are

Those with a short wavelength

Aluminum filtered rays

Those with ling wavelengths

High energy waves

Sonic waves