1.
All ionizing radiations cause damage to living tissues. although very little radiation is used in dentistry, damage to the cells does occur.
Correct Answer
A. Both are true
Explanation
Both statements in the question are true. Ionizing radiations, including those used in dentistry, do cause damage to living tissues. Although the amount of radiation used in dentistry is minimal, it can still lead to cell damage. Therefore, both statements are correct.
2.
What specific mechanism of radiation may result in the formation of hydrogen peroxide when xray energy is absorbed by patients?
Correct Answer
B. Free radical formation created by the ionization of water may occur
Explanation
When X-ray energy is absorbed by patients, ionization of water molecules can occur. This ionization process can lead to the formation of free radicals, which are highly reactive molecules with unpaired electrons. These free radicals can react with other atoms or molecules, including hydrogen peroxide, leading to its formation. Therefore, the specific mechanism of radiation that may result in the formation of hydrogen peroxide is the free radical formation created by the ionization of water.
3.
Where is the best place for you to view the radiograph that you used for the film screen contact test?
Correct Answer
C. Dimly lit room at a distance of 6 ft from the view box
Explanation
The correct answer is a dimly lit room at a distance of 6 ft from the view box. This is because radiographs are best viewed in a dimly lit environment to enhance the visibility of details and minimize glare. Additionally, viewing the radiograph from a distance of 6 ft allows for better assessment of the image as it provides a more accurate representation of the actual size and proportions of the structures being examined.
4.
The view box should emit a uniform subbdued light when it is functioning properly. permanently discolored plexiglas surfaces and blackened fluorescent light bulbs must be replaced.
Correct Answer
A. Both are true
Explanation
The explanation for the given correct answer, which is "both are true," is that when the view box is functioning properly, it should emit a uniform subdued light. This means that the light should be evenly distributed and not too bright or harsh. Additionally, if the plexiglas surfaces are permanently discolored and the fluorescent light bulbs are blackened, they must be replaced. This implies that these issues indicate a malfunction or damage to the view box, further supporting the statement that both statements are true.
5.
The perform the coin test, the film and coin are exposed to
Correct Answer
A. The safelight
Explanation
The correct answer is the safelight. In a darkroom, a safelight is used to provide illumination without affecting the light-sensitive film. The safelight emits a specific wavelength of light that does not expose the film, allowing the photographer to handle and inspect the film without causing any damage. Using any other light source, such as the darkroom ceiling or white light, the light with the darkroom door open, or no light at all, would result in the film being exposed and potentially ruined.
6.
To conduct the coin test, the film and coin are exposed for
Correct Answer
B. 3 or 4 minutes
Explanation
The correct answer is 3 or 4 minutes. This duration is sufficient to expose both the film and the coin to the necessary conditions for the coin test. It allows enough time for any reactions or changes to occur on the film surface when it comes into contact with the coin. A shorter duration may not provide accurate results, while a longer duration may lead to unnecessary exposure or potential damage to the film.
7.
If the image of the coin appears on the processed radiograph after the coin test
Correct Answer
B. The safelight is not safe to use with that type of film
Explanation
If the image of the coin appears on the processed radiograph after the coin test, it means that the safelight is not safe to use with that type of film. The purpose of the coin test is to determine if the safelight is emitting the correct wavelength of light that won't affect the film. If the image of the coin is visible, it indicates that the safelight is emitting light that is exposing the film and causing unwanted images to appear. Therefore, it is not safe to use the safelight with that type of film.
8.
If the processor is functioning properly the results of the automatic processor test films will be that
Correct Answer
A. The unexposed film appears clear and dry and the film exposed to light appears black and dry
Explanation
When the processor is functioning properly, the unexposed film should appear clear and dry because it has not been exposed to any light. On the other hand, the film exposed to light should appear black and dry because the light causes the film to react and darken. This is the expected result when the processor is working correctly.
9.
A reference radiograph is used to evaluate
Correct Answer
D. Developer strength
Explanation
A reference radiograph is used to evaluate the developer strength. The developer strength refers to the concentration of the developing solution used in radiography. It is important to have the correct developer strength in order to obtain accurate and clear radiographic images. The reference radiograph serves as a standard or benchmark for comparing the quality of the developed radiographs. By comparing the developed radiographs with the reference radiograph, one can determine if the developer strength is appropriate or if adjustments need to be made.
10.
To create a reference which of the following must be fresh
Correct Answer
A. Film developer fixer
Explanation
To create a reference, the film developer fixer must be fresh. This is because the film developer fixer is responsible for developing the film and fixing the image. If the developer fixer is not fresh, it may not properly develop the film or fix the image, resulting in a poor or unusable reference. Therefore, it is important to ensure that the film developer fixer is fresh when creating a reference.
11.
Prior to using the developer each day you compare the reference sheet to a test film that you developed to check to see if the developer chemicals depleted. what are you comparing when you look at the two films
Correct Answer
D. Density
Explanation
When comparing the reference sheet to the test film, you are checking for any changes in density. Density refers to the darkness or lightness of an image on the film. By comparing the density of the reference sheet to the test film, you can determine if the developer chemicals have depleted. If there is a significant difference in density between the two films, it indicates that the developer chemicals may need to be replenished.
12.
When the step wedge technique is used to evaluate developer strength, and the density on the daily radiograph differs from that on the standard radiograph by more than ___________ steps, the developer solution is depleted
Correct Answer
A. Two
Explanation
When the step wedge technique is used to evaluate developer strength, and the density on the daily radiograph differs from that on the standard radiograph by more than two steps, it indicates that the developer solution is depleted. This means that the developer solution is no longer able to produce the desired level of density on the radiograph, indicating that it needs to be replenished or replaced.
13.
Quality assurance monitoring includes a detailed log of all tests performed. a monitoring schedule should be posted in the dental office
Correct Answer
A. Both are true
Explanation
The explanation for the given correct answer is that quality assurance monitoring does indeed include a detailed log of all tests performed. This log helps track the testing process and provides a record of the tests conducted. Additionally, it is recommended to have a monitoring schedule posted in the dental office to ensure that the monitoring activities are carried out regularly and consistently. This schedule helps in organizing and planning the monitoring activities effectively. Therefore, both statements are true.
14.
Which of the following films would most likely appear black
Correct Answer
C. A film exposed to light
Explanation
A film exposed to light would most likely appear black because when light hits the film, it causes a chemical reaction that darkens the film. This is because the light exposure activates the silver halide crystals in the film, which then react with the developing chemicals to create the black and white image.
15.
The possibility of exposure of radiographic film to white light can be reduced by
Correct Answer
C. Not unwrapping the film in a room with white light
Explanation
The correct answer is not unwrapping the film in a room with white light. This is because white light can cause exposure of radiographic film, so it is important to avoid unwrapping the film in a room with white light. By keeping the film wrapped and not exposing it to white light, the possibility of exposure can be reduced.
16.
An underexposed receptor results from
Correct Answer
A. Insufficient exposure time
Explanation
An underexposed receptor occurs when the exposure time is not sufficient. This means that the receptor did not receive enough radiation during the exposure, resulting in a darker image. Insufficient exposure time can be caused by factors such as a short exposure duration or a low radiation output from the X-ray machine.
17.
To prevent underexposure, check and increase ______________ as needed
Correct Answer
A. Exposure time mA kV
Explanation
To prevent underexposure, it is necessary to check and increase the exposure time, mA, and kV as needed. This means that all three factors should be considered and adjusted accordingly to ensure that the image is properly exposed. Increasing the exposure time allows for more radiation to reach the image receptor, increasing the mA increases the amount of radiation produced, and increasing the kV increases the penetrating power of the radiation. By adjusting these factors, underexposure can be prevented and a properly exposed image can be obtained.
18.
To correct a dental image where apices do not appear,
Correct Answer
B. The teeth must be firmly in contact with the bite-block
Explanation
In order to correct a dental image where apices do not appear, it is important to ensure that the teeth are firmly in contact with the bite-block. This is because the bite-block helps to stabilize the teeth and keep them in the correct position for imaging. By ensuring that the teeth are firmly in contact with the bite-block, it helps to prevent any movement or shifting of the teeth during the imaging process, which can result in a more accurate and clear image.
19.
When the occlusal plane appears tipped or tilted, the error is a
Correct Answer
C. Dropped receptor corner
Explanation
When the occlusal plane appears tipped or tilted, the error is a dropped receptor corner. This means that one of the corners of the dental X-ray receptor has not been properly positioned, causing the image to be distorted and the occlusal plane to appear tilted. This error can occur if the receptor is not properly aligned with the teeth or if it slips during the X-ray procedure.
20.
To prevent a dropped receptor corner
Correct Answer
D. Make certain the edge of the receptor is placed parallel to the incisal-occlusal surfaces of the teeth
Explanation
Placing the edge of the receptor parallel to the incisal-occlusal surfaces of the teeth helps to prevent a dropped receptor corner. This ensures that the receptor is properly aligned with the teeth and reduces the risk of the receptor slipping or falling out of position during the imaging process. By maintaining parallel alignment, the receptor remains stable, providing accurate and clear images for diagnosis and treatment planning.
21.
To avoid overlapped contacts on periapical image
Correct Answer
C. Direct the xray beam through the interproximal regions
22.
Long distored teeth appear on the image when
Correct Answer
B. The vertical angulation is insufficient
Explanation
When the vertical angulation is insufficient, it means that the X-ray beam is not directed perpendicular to the teeth. This can result in distorted teeth appearing on the image. Insufficient vertical angulation causes foreshortening of the teeth, making them appear shorter than their actual length. This occurs because the X-ray beam is angled too steeply, causing the image to be compressed vertically. As a result, the teeth may appear distorted and inaccurate measurements may be obtained.
23.
A cone-cut occurs when
Correct Answer
C. The PID was not properly aligned with the periapical receptor holder
Explanation
The correct answer is "the PID was not properly aligned with the periapical receptor holder." A cone-cut occurs when the position-indicating device (PID) is not aligned properly with the periapical receptor holder. This misalignment results in part of the X-ray beam being blocked, causing an incomplete exposure of the receptor. This can lead to inaccurate or incomplete diagnostic information.
24.
A thin radiolucent line appears of the film with
Correct Answer
A. Film creasing
Explanation
The correct answer is film creasing. This is because a thin radiolucent line appearing on the film is indicative of a crease or fold in the film. Film bending would result in a more pronounced distortion, while double exposure would show overlapping images on the film. Patient movement would cause blurring or ghosting of the image, rather than a thin radiolucent line.
25.
The appearance of a patients finger on the image is called a
Correct Answer
B. pHalangioma
Explanation
A phalangioma refers to the appearance of a patient's finger on an image. It is a term used to describe an abnormal growth or tumor in the finger. This could be a benign condition such as a hemangioma, which is a type of blood vessel tumor, or it could be a different type of tumor like a myxoma or pericytoma. Without further information, it is difficult to determine the exact nature of the appearance, but phalangioma is a general term that encompasses these possibilities.
26.
To avoid a double exposure
Correct Answer
C. Always separate exposed and unexposed film and PSP receptors
Explanation
To avoid a double exposure, it is important to always separate exposed and unexposed film and PSP receptors. This ensures that the unexposed film and receptors do not come into contact with the already exposed ones, preventing any overlapping or double exposure of the images. By keeping them separate, the risk of obtaining inaccurate or unclear radiographic images is reduced, allowing for more accurate diagnosis and treatment planning.
27.
Your left premolar bitewing image is lighter than the rest of the images and has a herringbone pattern. what can you do to prevent this problem from occuring? when the film is reversed,
Correct Answer
C. Make sure the film side is facing the PID
Explanation
To prevent the left premolar bitewing image from being lighter and having a herringbone pattern, it is important to make sure that the film side is facing the PID (Position-Indicating Device). This means that the film should be positioned correctly in relation to the X-ray machine, ensuring that the X-ray beam passes through the film properly. If the film is facing the wrong way, it can result in improper exposure and artifacts like the herringbone pattern.
28.
You have noticed that your maxillary premolars are elongated, how would you fix this problem
Correct Answer
C. Increase vertical angulation
Explanation
To fix the problem of elongated maxillary premolars, you would need to increase the vertical angulation. This means tilting the X-ray receptor or film in a way that allows the X-ray beam to be directed more downwards towards the teeth. By increasing the vertical angulation, the X-ray image will capture a shorter length of the teeth, reducing the appearance of elongation. This adjustment helps to obtain a more accurate and proportional representation of the teeth on the X-ray image.
29.
You are creating a cleaning log for panoramic intensifying screens. how frequently should the screes be cleaned
Correct Answer
C. Monthly
Explanation
The screens should be cleaned monthly to maintain their effectiveness and ensure clear and accurate imaging. Cleaning them on a regular basis helps remove dust, dirt, and other contaminants that can accumulate and affect the quality of the images produced. Monthly cleaning also allows for early detection of any damage or wear on the screens, allowing for timely repairs or replacements if needed.
30.
A film-screen contact test is used to test the
Correct Answer
C. Cassette holder for extra oral films
Explanation
A film-screen contact test is used to test the cassette holder for extra oral films. The film-screen contact test is performed to ensure that there is proper contact between the film and the intensifying screens inside the cassette holder. This is important because if there is poor contact, it can result in a decrease in image quality and diagnostic accuracy. Therefore, by conducting the film-screen contact test, one can verify the functionality and effectiveness of the cassette holder for extra oral films.
31.
The indirect theory proposes that
Correct Answer
A. Toxins are created from the formation of free radicals
Explanation
The indirect theory proposes that toxins are created from the formation of free radicals. Free radicals are highly reactive molecules that can cause damage to cells and DNA. When ionizing radiation strikes critical areas within cells, it can lead to the formation of free radicals. These free radicals can then cause changes to the DNA of a cell, leading to the creation of toxins. This suggests that indirect injuries, caused by the formation of free radicals, occur more frequently than direct injuries.
32.
According to the dose-response curve, when dose and damage are plotted on a graph, a ______________ relationship is seen
Correct Answer
B. Linear, nonthreshold
Explanation
According to the dose-response curve, when dose and damage are plotted on a graph, a linear, nonthreshold relationship is seen. This means that as the dose increases, the damage also increases in a linear manner, without a threshold level below which no damage occurs. In other words, there is a direct and proportional relationship between the dose and the damage, regardless of the dose level.
33.
Stochastic biologic effects from radiation
Correct Answer
B. Occur as a result of exposure, but severity is not determined by the dose
Explanation
Stochastic biologic effects from radiation occur as a result of exposure, meaning that they only happen when a person is exposed to radiation. However, the severity of these effects is not determined by the dose of radiation received. This means that even low doses of radiation can potentially cause significant damage to cells or even cell death, without the severity of the effects being directly proportional to the dose. Unlike deterministic effects, which have a dose threshold and their severity increases with higher doses, stochastic effects do not have a threshold and their occurrence is random.
34.
Which of the following is an example of stochastic effects
Correct Answer
B. Cancer
Explanation
Cancer is an example of stochastic effects because it is a random and unpredictable outcome that can occur as a result of exposure to radiation. Stochastic effects do not have a threshold level of exposure and the probability of occurrence increases with higher levels of exposure. In the case of cancer, the development of the disease is not guaranteed even with low levels of radiation exposure, but the risk increases with higher doses. This is in contrast to deterministic effects, where there is a direct cause and effect relationship between exposure and the severity of the effect.
35.
Your patient was out in the hot, bright sun yesterday. while in the sun she began expirencing pain and noticed her skin was bright red. shortly after arriving home, she began to experiance chills, nausea, severe pain aand blistering. why would your patient experience the symptoms so quickly?
Correct Answer
A. The latent period was decreased by the increased dose and dose rate
Explanation
The symptoms experienced by the patient, such as pain, blistering, chills, and nausea, occurred quickly because the latent period was decreased by the increased dose and dose rate. This means that the patient was exposed to a higher amount of radiation in a shorter period of time, leading to a faster onset of symptoms. The increased dose and dose rate can cause more damage to the cells and tissues, resulting in the rapid manifestation of symptoms.
36.
Cellular injuries following the latent period may includ 1. cell death 2.cessation of mitotic activity and 3. abnormal mitotic activity
Correct Answer
A. 1, 2 ,3
Explanation
Cellular injuries following the latent period may include cell death, cessation of mitotic activity, and abnormal mitotic activity. This means that after a certain period of time, cells may undergo death, stop dividing, or exhibit abnormal division. These cellular injuries can occur due to various factors such as physical trauma, chemical exposure, or genetic abnormalities. It is important to understand and study these cellular injuries to develop effective treatments and preventive measures for various diseases and conditions.
37.
__________ refers to the total amount of radiation that is reveived or absorbed
Correct Answer
A. Total dose
Explanation
Total dose refers to the total amount of radiation that is received or absorbed by an object or organism. It is a measure of the cumulative exposure to radiation over a specific period of time. The total dose takes into account both the intensity and duration of the radiation exposure. This measurement is important in assessing the potential health effects of radiation and determining appropriate safety measures.
38.
More radiation damage takes place with high dose rates. because a rapid delivery of radiation does not allow time for cellular damage to be repaired
Correct Answer
A. Both are true
Explanation
Both statements are true. High dose rates of radiation result in more radiation damage because the rapid delivery of radiation does not allow enough time for cellular damage to be repaired. This is because higher dose rates overwhelm the cellular repair mechanisms, leading to increased damage.
39.
Which types of cells are more sensitive to radiation
1. rapidly dividing 2. slowly dividing 3. young 4. old
Correct Answer
A. 1 and 3
Explanation
Rapidly dividing cells and young cells are more sensitive to radiation. Rapidly dividing cells are more susceptible to radiation because radiation damages DNA, and rapidly dividing cells have a higher rate of DNA replication. Young cells, which are still in the early stages of development, also have a higher sensitivity to radiation as they are more actively dividing and growing compared to older cells.
40.
Which of the following is associated with long-term radiation effects
Correct Answer
B. Small amounts of radiation absorbed over a long period
Explanation
Small amounts of radiation absorbed over a long period is associated with long-term radiation effects. This is because prolonged exposure to low levels of radiation can cause cumulative damage to the body's cells and tissues, leading to symptoms such as diarrhea, hair loss, and hemorrhage. Acute radiation syndrome, on the other hand, refers to the immediate effects of high doses of radiation and is not associated with long-term effects.
41.
Which of the following is a sign or symptom of acute radiation syndrome
Correct Answer
C. Hair loss
Explanation
Hair loss is a sign or symptom of acute radiation syndrome. Exposure to high levels of radiation can damage the hair follicles, leading to hair loss. This is because radiation affects rapidly dividing cells, and hair follicles are one of the fastest dividing cells in the body. Therefore, hair loss is commonly observed in individuals who have been exposed to high levels of radiation, such as those undergoing radiation therapy for cancer treatment or those involved in nuclear accidents.
42.
Which of the following cells would be the most sensitive to xrays
Correct Answer
D. Blood
Explanation
Blood cells would be the most sensitive to X-rays because they are constantly dividing and replicating, making them more susceptible to damage from radiation. Additionally, blood cells are located throughout the body and are in direct contact with X-rays, increasing their exposure. Nerve cells, bone cells, and muscle cells are not as actively dividing as blood cells, making them less sensitive to the effects of X-rays.
43.
Which of the following is the least sensitive to xrays
Correct Answer
B. Salivary glands
Explanation
Salivary glands are the least sensitive to X-rays compared to the other options. X-rays are a form of ionizing radiation that can cause damage to living tissues. Bone marrow, lymphoid tissue, and intestines are all highly sensitive to X-rays because they contain rapidly dividing cells that are more susceptible to radiation damage. Salivary glands, on the other hand, do not contain as many rapidly dividing cells, making them less sensitive to X-rays.
44.
The traditional unit of dose is called
Correct Answer
B. The radiation absorbed dose
Explanation
The correct answer is "the radiation absorbed dose." The term "radiation absorbed dose" refers to the amount of radiation energy that is absorbed by a material or tissue. It is a unit used to measure the amount of radiation received by an object or person. The other options mentioned in the question, such as the roentgen and the gray, are also units of radiation measurement, but they do not specifically refer to the dose.
45.
You could be exposed to each of these radiation sources in your daily activities. which of these sources is human-made
Correct Answer
B. Atomic fallout
Explanation
Atomic fallout is a human-made source of radiation. It refers to the radioactive particles that are released into the atmosphere as a result of nuclear explosions or accidents. These particles can contaminate the air, water, and soil, posing a significant health risk to humans. Unlike radon gas, terrestrial radiation, and radioactive potassium, which occur naturally, atomic fallout is a direct consequence of human activities involving nuclear technology.
46.
______________ are the single largest contributor to artificial radiation exposure
Correct Answer
B. Medical radiation
Explanation
Medical radiation is the single largest contributor to artificial radiation exposure. This is because medical procedures that involve the use of radiation, such as X-rays, CT scans, and radiation therapy, are common and widespread. These procedures are essential for diagnosing and treating various medical conditions, but they also expose individuals to radiation. Compared to other sources such as consumer products, fallout from atomic weapons, and the nuclear fuel cycle, medical radiation is responsible for the highest levels of artificial radiation exposure.
47.
The potential risk of dental radiography inducing a fatal cancer in an individual is about ___________
Correct Answer
D. 3/1,000,000
Explanation
The potential risk of dental radiography inducing a fatal cancer in an individual is estimated to be 3 in 1,000,000. This means that the likelihood of dental radiography causing a fatal cancer is very low, with only 3 cases expected to occur out of every 1,000,000 individuals who undergo the procedure.
48.
A 1 in 1 million risk of fatal outcome is associated with which of the following activities
Correct Answer
D. All three activities
Explanation
All three activities (riding 10 miles on a bike, riding 300 miles in an auto, riding 1000 miles in an airplane) are associated with a 1 in 1 million risk of a fatal outcome. This means that the likelihood of a fatal outcome is the same for all three activities, despite the differences in distance and mode of transportation.
49.
The use of F speed film instead of D speed film reduces the absorbed does by _____ %
Correct Answer
D. 60
Explanation
The use of F speed film instead of D speed film reduces the absorbed dose by 60%. This means that F speed film is more efficient at reducing the amount of radiation absorbed compared to D speed film. This is important in situations where minimizing radiation exposure is critical, such as in medical imaging or industrial radiography. By using F speed film, the absorbed dose can be significantly reduced, leading to improved safety and reduced health risks for individuals exposed to radiation.
50.
Which of the following combinations will result in the lowest absorbed dose for the patient from a 20-film ,series of dental radiographs
Correct Answer
B. Rectangular collimation with digital sensor
Explanation
Rectangular collimation with a digital sensor will result in the lowest absorbed dose for the patient from a 20-film series of dental radiographs. Rectangular collimation restricts the X-ray beam to only expose the necessary area, reducing unnecessary radiation exposure to the patient. Additionally, digital sensors are more sensitive and require less radiation compared to traditional film, further minimizing the absorbed dose.