Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Dental R Unit I > Quiz 1 > Flashcards

Quiz 1 Flashcards

(73 cards)

Start Studying
1
Q

Which of the following is impervious to the penetration
of x-rays?

A

Lead

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

The quality of energy that is produced by the central
x-ray is determined by the:

A

kVp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

The size of the collimated x-ray beam for an intraoral
radiograph is measured at the patient’s skin at:

A

2.75 inches

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the purpose of the lead collimator in the
dental x-ray tube head?

A

Retards the size of the x-ray beam

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

The maximum protection for the patient is provided by a:

A

Lead shielded, open-ended P.I.D.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How does filtration of the x-ray beam protect the patient?

A

Elimination of weak wavelengths from the x- ray beam

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

A woman who is pregnant should:

A

Avoid x-rays during the first trimester of pregnancy.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Where does secondary radiation emanate from?

A

All of the above

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

When exposing an intraoral radiograph, where should
the operator stand in order to be in a protected area?

A

At least six (6) feet from the x-ray tube head

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Proper collimation for the film size and target–film distance will

A

Decrease the radiation received by the
patient.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

The quality, or penetrating power, of secondary radiation is

A

Less than that of primary radiation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

To avoid exposure to secondary radiation, the operator should stand

A

At least 6_____ from the x-ray tube head

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

The dental assistant’s goal in radiation protection is zero occupational exposure. This is accomplished by

A
  1. Never holding the film for the patient.
  2. Always being 6 feet away from the machine.
  3. Working in a shielded area.
  4. Wearing a film badge.

all of the above

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

After each use, the lead lap apron must be

A

Draped over a support rod unfolded.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

The best technique for reducing the radiation exposure to both patient and operator is the use of

A

Fast film

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

If the mA is increased while the kVp and the exposure time are kept constant, the resulting films will

A

Be darker

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

For maximum penetration of x-rays, which of the following combinations would you select?

A

90 kVp and 10 mA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Which of the following is not a main component of a panoramic x-ray unit?

A

Panoramic film

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Why does digital radiograph require less radiation than traditional x-rays?

A

It uses lower wave-length radiation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Which type of radiation initially comes from the x rays tube?

A

Primary radiation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

A lead apron with a thyroid collar will protect a patient from what type of radiation?

A

Scatter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

The x-ray tube has a positive side called the anode and a negative side called:

A

Cathode

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

The production or boiling off of electrons from the heated tungsten filament is called:

A

Thermionic emission effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

The unit of measurement used to described the amount of electric current flowing through a circuit is called:

A

Ampere

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
The term used to describe the electric potential or force that drives an electric current through a circuit is called:
Voltage
26
The target of the x-ray tube is also called the:
Focal spot
27
The x-ray at the center of the beam is referred to as the
Central ray
28
The quality or penetrating power of the x-ray beam is controlled by:
Kilovoltage
29
The range _____ is used for the dental radiograph.
65 to 100 kVp
30
What determines the number of x-rays produced in a given exposure time period by controlling the heating of the tungsten filament?
Milliamperage
31
Miliamperage higher than 15 would produce too many electrons bombarding the target and too much heat
True
32
Federal regulations require that long non-penetrating rays are removed from the primary beam. This is accomplished by a:
Filter
33
Federal regulation require that for dental x-ray machines operating above 70 kVp, the thickness of the filter must be
2.5 mm thick
34
The size and shape of the x-ray beam as it leaves the tube head are restricted by
Collimator
35
The diaphragm is made out of:
Lead
36
According to federal regulations, the size and shape of the x-rays beam should not exceed ________in diameter.
2.75 inches
37
The radiation that originates from the target of the x- ray machine is referred to as:
Primary radiation
38
The radiation that results from the interaction of primary radiation with matter is called:
Secondary radiation
39
The degree of blackness or darkness on a radiograph is referred to as:
Density
40
The difference in the degree of blackness or darkness between adjacent areas on a processed radiograph is referred to as:
Contrast
41
The object contrast is determinate by:
A. The thickness of the object B. The density of the object C. Chemical composition of the object D. Quality of the x-ray beam E. Scatter radiation F. All of the above
42
The image difference between the films produced at the different kVp choices in the dental range is the resulting contrast.
True
43
High contrast film will appear:
Black and white and short scale A and C
44
As you increase your kVp, the contrast will:
Decrease
45
Scatter radiation causes:
Film fog
46
Film contrast is determined by:
A. The amount of radiation transmitted B. The type of film C. Intensifying screens D. Film processing E. All of the above
47
The distance between the focal spot at the anode and the film in the patient’s mouth is referred to as:
A. Focal-film distance B. Anode-film distance Both
48
The measurement of ionization in the air is referred to as:
Roentgen
49
The radiation that is produced by the machine is referred to as:
Exposure
50
Radiation that escapes through the protective shielding of the x-ray tube head is called:
Head leakage
51
The operator should stand a minimum of ____feet away from the tube head.
6 feet
52
The maximum permissible dose of whole body radiation for dental personnel is:
5 Rem per year
53
The maximum whole body dose that a worker is allowed is:
100 millirem per week
54
If the proper exposure time at 15 mA and 65 kVp is 0.25 seconds and an 8 inch FFD is used, what would the exposure time be at 16 inches?
1.0 seconds
55
A ______ is a personnel monitoring device that can be worn by the staff to measure radiation received.
Dosimeter
56
When an x-ray causes an electron to be ejected from its orbit, the effect is called:
Photoelectric effect
57
When the electrons bombard the target in the x-ray tube, what percent of the energy produced is radiation?
1%
58
When an x-ray causes an electron to be ejected from its orbit, it is called:
Ionization
59
Primary radiation is the energy contained by the x- rays that come from the target of the x-ray tube.
True
60
Secondary radiation is defined as radiation that comes from any matter being struck by primary radiation.
True
61
The radiation dose is the measure of ionization that is in the air.
False
62
The positive side of the dental x-ray tube is called the
ANODE
63
The ___________ is the unit of measure used for measuring the exposure the air.
ROENTGEN
64
X-rays of longer wavelengths that have low penetration are called _____________.
SOFT X RAYS.
65
The distance from the crest of one wave to the crest of another wave is called
WAVELENGTH.
66
The legal limit of how long a dentist must keep a patient’s x-rays is _____ years.
7 years
67
The x-ray at the center of the primary beam is called the
Central ray
68
________________________ The electrical pressure or force that drives the current through a circuit of the x-ray machine.
VOLTAGE
69
________________________ A unit of electromotive force or potential.
Volt
70
_____ a device that is used to measure density and contrast
Step wedge
71
________________________ A device used for measuring the electromotive force across the x-ray tube.
VOLMETER
72
_______________________ Electric device that is capable of increasing or decreasing voltage.
TRANSFORMER
73
______________________Part of the primary beam that is permitted to emerge from the housing of the tube.
USEFUL RADIATION

Dental R Unit I (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions