1.
The harmful effects of radiation on human tissues are
Correct Answer
D. Cumulative
Explanation
The effects of repeated exposure to radiation are cumulative and can result in many different disorders such as cancer, cataracts, leukemia, and genetic abnormalities.
2.
The protective lead apron must be impregnated with how much lead?
Correct Answer
C. 0.25 mm
Explanation
The lead apron must be impregnated with 0.25 mm of lead to be effective in shielding out the radiation.
3.
You have a patient who had read articles describing the hazards of medical/dental radiation and is not sure about letting you take X-rays on her. Based on what you now know, how could you explain the procedures in a way that would be reassuring?
Correct Answer
E. All of the above
Explanation
If you have a patient with concerns about radiation exposure, you should explain that you are using a lead apron and lead thyroid shield, you are using the long cone paralleling technique, and you take radiographs only when a need is indicated by clinical examination and not based on an arbitrary time schedule.
4.
What do filters do in the X-ray beam?
Correct Answer
E. Reduce patient radiation dose and remove the long waves
Explanation
Aluminum filters are used in the PID to filter out the long wanes. Only the short waves are useful in making an image on a film. Therefore, the filter removes the long waves and the patient receives less radiation.
5.
The X-ray photons generated by the dental X-ray machine have
Correct Answer
B. Many different wavelengths
Explanation
The X-ray photons produced in the tube head have many different wave lengths.
6.
What is the recommened collimation of the radiation beam at the patient's skin surface?
Correct Answer
B. 2.75 inches
Explanation
The recommended collimation or restriction of the size of the X-ray beam at the patient's face is 2.75 inches.
7.
What does the ALARA concept stand for?
Correct Answer
A. As low as reasonably achievable
Explanation
The ALARA concept stands for "as low as reasonably achievable." This concept is used in radiation protection to minimize exposure to radiation by implementing measures that are practical and feasible. The goal is to keep radiation doses as low as possible while still allowing for the necessary tasks to be performed. This approach ensures that radiation risks are minimized and that individuals are protected from unnecessary exposure.
8.
Which of the following devices is an example of personnel monitoring?
Correct Answer
E. A, b, and c
Explanation
Film badges, pocket dosimeters, and film rings are all example of personnel monitoring devices that measure the dose of radiation received by the members of the dental team.
9.
The transfer of energy as it passes through matter is called
Correct Answer
D. Absorption
Explanation
The energy of the X-ray beam is transferred to the material through which it passes. This transfer of energy is called absorption.
10.
What is it called when a lead disc is used for the elimination of the peripheral portion of the X-ray beam?
Correct Answer
B. Collimation
Explanation
Collimation means that a lead disc is used for the elimination of the peripheral portion of the X-ray beam. The lead disc is called the collimator. It restricts the size of the X-ray beam at the patient's face.
11.
Which molecular changes occur in a living organsim being struck by photons?
Correct Answer
E. All of the above
Explanation
When a living organism is struck by photons, the molecules are broken into smaller pieces, they form new bonds within themselves and with other molecules, and some molecular bonds are disrupted.
12.
What is the correct vertical angulation used when taking a bitewing radiograph?
Correct Answer
B. +10 degrees
Explanation
+10 degrees vertical angulation is the correct vertical angulation for taking bitewing radiographs to produce minimal geometric distortion and open the contacts between the teeth.
13.
In the bisecting the andle technique, where is the vertical angel of the central beam directed?
Correct Answer
D. Perpendicular to the line bisecting the angle made by the long axis of the tooth and the film
Explanation
In the bisecting the angle technique, the vertical angle of the beam is directed perpendicular to the line that bisects the angle made by the film and the long axis of the tooth being radiographed.
14.
What is true of a full-mouth X-ray series?
Correct Answer
A. Always has periapical and bitewings
Explanation
A full-mouth X-ray series always includes periapical and bitewing films. These films are essential for capturing detailed images of the teeth and surrounding structures. The other options in the question, such as the minimum number of films and the possibility of using a panoramic film as a replacement, are not necessarily true for a full-mouth X-ray series. The number of films and the specific types of X-rays needed can vary based on individual selection criteria and the size of the patient's mouth. Therefore, the correct answer is that a full-mouth X-ray series always includes periapical and bitewings, and the need and number of films can vary based on selection criteria and mouth size.
15.
In dental radiography, what infection control procedures are included?
Correct Answer
D. Both a and b
Explanation
In dental radiography, the Snap-A-Ray film holders and XCP film holders are sterilized and the treatment room is disinfected. No antiseptic agents are used.
16.
What is the safest postion for an operator while exposing an intraoral film?
Correct Answer
B. Behind a lead barrier
Explanation
Standing behind the lead barrier is the safest place for the operator while exposing intraoral films.
17.
What does immersing the contaminated exposed film packet in a disinfecting solution do?
Correct Answer
B. Destroys the image
Explanation
Exposed film should never be immersed in a disinfecting solution. Immersing them in any liquid will destroy the image. However, it is acceptable to wipe the exposed films with a dry paper towel to remove any saliva or blood.
18.
What nees to happen wheeen exposing a full-mouth set of radiographs?
Correct Answer
D. The exposure button should be covered with a plastic barrier
Explanation
Covering the exposure button with a plastic barrier is part of the infection control protocol for exposing X-rays.
19.
Where in the X-ray head does thermionic emission take place?
Correct Answer
B. Tungsten filament
Explanation
Thermionic emission, which is when the electrons are boiled off of the tungsten filament, takes place in the cathode at the tungsten filament.
20.
Which radiographic technique records the most accurate image of crowns, roots, and supporting structures?
Correct Answer
C. Periapical film
Explanation
The periapical intraoral film records the most accurate image of crowns, roots, and supporting structures.
21.
The bicuspid/premolar bitewing radiograph should be placed to include which of the following anatomic structures?
Correct Answer
B. The distal half of the mandibular cuspid
Explanation
Proper film placement for the bicuspid/premolar bitewing radiograph must include the distal half of the mandibular cuspid. This way the bicuspid will appear in the center of the radiograph
22.
What is the primary diagnotic use of a bitewing radiograph?
Correct Answer
E. Check for interproximal decay and crestal bone levels.
Explanation
The primary diagnostic use of a bitewing radiograph is to check for interproximal decay and examine the crestal bone levels.
23.
The size-1 film would most likely be used to radiograph which of the following areas on an adult patient?
Correct Answer
A. Incisors and cuspids
Explanation
In a 20-film mount full-mouth set of X-rays, the central incisors, lateral incisors, and cuspids are radiographed using a size-1 film.