Final Flashcards
The smaller the silver halide crystals in the emulsion of an intraoral film, the faster the film speed.
Faster film speed reduces radiation exposure to the patient.
A. Both statements are true.
B Both statements are false.
C The first statement is true, and the second statement is false.
D The first statement is false, and the second statement is true.
D. The first statement is false, and the second statement is true.
Which of the following statements BEST describes the anomaly in the image shown below?
A Foreshortening of the root, vertical angle too great
B Foreshortening of the root, vertical angle not enough
C Incomplete apical development of the root
D Internal resorption of the root
E External resorption of the root
E. External resorption of the root
A periapical (PA) image is needed on the maxillary left premolar area. The patient presents with a large maxillary torus. Using the paralleling, or right-angle, technique, the image receptor film or sensor is to be placed
A distal to the maxillary premolar area.
B mesial to the maxillary premolar area.
C as close to the maxillary left premolar as possible.
D as far from the maxillary left premolar as possible.
D. as far from the maxillary left premolar as possible.
A periapical image of the maxillary right molar area is needed, but patient has a shallow palate, and the first image taken misses the apices of the teeth. To correct this error, using the paralleling technique, an acceptable image can be obtained by moving the PID in a:
A 20-degree difference in the horizontal angulation toward the mesial surfaces.
B 20-degree difference in the horizontal angulation toward the distal surfaces.
C positive 20-degree difference in the vertical angulation.
D negative 20-degree difference in the vertical angulation.
E direction in which the central ray is perpendicular to the image receptor.
C. +20-degree difference in the vertical angulation.
A radiographic image will have increased density if the operator:
A increases the kVp.
B decreases the kVp.
C decreases the milliampere (mA).
D increases the distance of the x-ray source to the image receptor.
A. increases the kVp.
Absorption:
Process of transferring energy of x-rays to atoms of material through which the x-ray beam passes
The beam of x-rays passing through matter is
weakened and gradually disappears.
(tooth absorbs energy = turns white)
According to the SLOB rule, the position of objects can be determined if the tube head is shifted in a mesial direction. The lingual object moves distally, and the buccal object moves mesially.
A. Both statements are true.
B Both statements are false.
C The first statement is true, and the second statement is false.
D The first statement is false, and the second statement is true.
B. Both statements are false.
All of the following are examples of radiosensitive cells EXCEPT one.
Which one is the EXCEPTION?
A. Cells with higher metabolism
B Cells with high mitotic activity
C Older, mature cells
D Primitive, nonspecialized cells
C. Older, mature cells
All of the following decrease radiation exposure to the patient EXCEPT one. Which one is the EXCEPTION?
A Thyroid collar
B F-speed film in place of D-speed film
C 8-inch PID in place of 16-inch PID
D Rectangular PID in place of round PID
E Collimator
C. 8-inch PID in place of 16-inch PID
All of the following factors increase image sharpness EXCEPT one. Which one is the EXCEPTION?
A Slower film speed
B Small focal spot
C Decreased penumbra
D Movement
D. Movement
All of the following phrases are consistent with the paralleling technique
EXCEPT one. Which one is the EXCEPTION?
A. A short PID is used.
B. It is the preferred method for taking radiographs.
C. The film is placed parallel to the long axis of the tooth.
D. The central ray is directed perpendicular to the tooth and the image receptor.
E. It produces images with the least magnification and dimensional distortion.
A. A short PID is used.
An x-ray beam has a half-value layer (HVL) of 6 mm. How many millimeters of aluminum are required to reduce the x-ray beam intensity by half?
A 2 mm
B 3 mm
C 6 mm
D 12 mm
C. 6 mm
Characteristic radiation:
(C)
Produced when a high-speed electron from the tube filament collides with an orbiting K-shell electron of the tungsten target.
Coherent scattering:
(B)
Incoming x-ray photon interacts with the electron by causing the electron to vibrate at the same frequency as the incoming x-ray photon.
Accounts for about 8% of the interactions of matter with the dental x-ray beam
Compton scattering:
Similar to the photoelectric effect
Incoming x-ray photon collides with an orbital electron and ejects it. But, only a part of the x-ray energy is transferred to the electron, and a new, weaker x-ray photon is formed and scattered in a new direction.
Accounts for about 60% of the interactions of matter with the dental x-ray beam.
Cone cutting has occurred on the coronal portion of a mandibular anterior PA image. The operator will correct this error by:
A. moving the image receptor more superiorly.
B moving the image receptor more inferiorly.
C moving the PID to completely cover the image receptor.
D adding more solution to the developer.
E adding more solution to the fixer.
C. moving the PID to completely cover the image receptor.
Considering exposure time during the production of x-rays, how many impulses are equivalent to 1⁄4 second?
A 1
B 6
C 15
D 30
E 240
C. 15
There are 60 impulses in a second, so to calculate impulses, multiply
60 x 1⁄4 second = 15 impulses
Erythema, nausea, diarrhea, hemorrhage, and loss of hair are
signs and symptoms seen with
A. chronic radiation exposure.
B acute radiation exposure.
C stochastic effects of radiation exposure.
D nonstochastic effects of radiation exposure.
E A and C
F B and D
F.
B. acute radiation exposure.
and
D. nonstochastic effects of radiation exposure.
Failing to follow radiation exposure patient guidelines would put a fetus at greatest risk in which trimester?
A First trimester
B Second trimester
C Third trimester
D Risk during all trimesters is equal
E There is no risk
A. First trimester
For each description of a radiograph’s appearance listed, select the most closely linked error. Each answer will only be used once.
Appearance Error
- Clear A. Film was developed in weak developer
- Light B. Film was exposed to white light
- Light film with “tire tracks” C. Film was placed backward
- Fogged D. Film was developed in a dark room with a crack in the safelight cover
- Black E. Film was not exposed to x-rays
- Clear E. Film was not exposed to x-rays
- Light A. Film was developed in weak developer
- Light film with “tire tracks” C. Film was placed backward
- Fogged D. Film was developed in a dark room with a crack in the safelight cover
- Black B. Film was exposed to white light
From the following list, select examples of stochastic effects of radiation exposure. (Select all that apply.)
A. Erythema
B Cancer
C Hair loss
D Genetic mutations
E Decreased fertility
B. Cancer
D. Genetic mutations
From the following list, select the three elements used in the x-ray tube.
A Bromine
B Copper
C Iron
D. molybdenum (focusing cup)
E Nickel
F Silver
G Tungsten
B. Copper
D molybdenum (focusing cup)
G Tungsten
From the following list, select the three statements
associated with digital imaging.
A. Sensors cannot be sterilized.
B A digital image is a two-dimensional representation of a 3-D object.
C Exposure times are 50% to 90% more than in traditional radiography.
D Digital imaging must be wired to function correctly.
E Assembled pictorial information with each gray value is
assigned a digit in binary code.
A. Sensors cannot be sterilized.
B. A digital image is a two-dimensional representation of a 3-D object.
E. Assembled pictorial information with each gray value is assigned a digit in binary code.
General/bremsstrahlung radiation:
Produced when high-speed electrons are stopped or slowed down by the tungsten atoms of the dental x-ray tube.
Identify # 10
X-Rays
Identify # 11
Port
Identify # 12
Oil
Identify # 14
Cathode (-)
Identify #1
Tube head
Identify #13
Copper stem
Identify #2
Low voltage transformer
Identify #3
Primary beam
Identify #4
High voltage transformer
Identify #5
Window
Identify #6
Collimator
Identify #7
Central ray
Identify #8
Filter
Identify #9
PID
Identify the almond-shaped radiolucent area in the image shown.
A Infraorbital foramen
B Nasal cavity
C Median palatal suture
D Maxillary sinus
E Incisive foramen
E. Incisive foramen
Identify the structure to which the arrows are pointing in the image shown.
A Maxillary sinus
B Maxillary tuberosity
C Genial tubercles
D Zygoma
D. Zygoma
In a darkroom, the correct lighting and distance from the working surface should be
A. a 60-watt bulb placed 6 feet away.
B. a 75-watt bulb placed 6 feet away.
C. a 7.5-watt bulb place 6 feet away.
D. a 30-watt bulb placed 8 feet away.
C. a 7.5-watt bulb place 6 feet away.
In a dental x-ray tube, the kinetic energy of electrons is converted to electromagnetic energy by the formation of:
General or bremsstrahlung radiation
German for “braking”
Characteristic radiation