Question 1

To retrieve extra supplies from an operatory drawer during a radiographic procedure:
a. open the drawer carefully and touch only the needed items to avoid cross-contamination.
b. remove one glove and open the drawer with the ungloved hand to retrieve th

Accepted Answer

Correct Answer:
d. don overgloves before touching the drawer or its contents.
Rationale:
To retrieve additional supplies during a radiographic procedure, don overgloves or ask for assistance. Opening the drawer and touching its contents with contaminat

Question 2

The collimator:
a. is always round.
b. restricts the size and shape of the x-ray beam.
c. is a solid piece of aluminum.
d. is fitted within the copper stem beneath the molybdenum cup.

Accepted Answer

Correct Answer:
b. restricts the size and shape of the x-ray beam.
Rationale:
The collimator is a diaphragm, usually lead, used to restrict the size and shape of the x-ray beam.

Question 3

The _____________ allows for the positioning of the tubehead.
a. control device
b. exposure button
c. extension arm
d. exposure light

Accepted Answer

Correct Answer:
c. extension arm
Rationale:
The extension arm of the x-ray machine is the component that suspends the x-ray tubehead and houses the electrical wires that extend from the control panel to the tubehead; its mobile arm helps in positioning

Question 4

Radiographs taken at a higher kilovoltage peak will have ______ compared to radiographs taken at a lower kilovoltage peak.
a. long-scale contrast
b. high contrast
c. short-scale contrast
d. multiple areas of black and white

Accepted Answer

Correct Answer:
a. long-scale contrast
Rationale:
Radiographs taken at a higher kilovoltage peak will have long-scale contrast versus radiographs taken at a lower kilovoltage peak.

Question 5

Dental x-rays do NOT:
a. create braking radiation.
b. make atoms radioactive.
c. disturb orbiting electrons.
d. have enough energy to produce ions.

Accepted Answer

Correct Answer:
b. make atoms radioactive.
Rationale:
Dental x-rays cannot make atoms radioactive; in other words, patients do not give off x-rays after exposure. Dental x-rays create braking radiation and can disturb orbiting electrons. X-rays have en

Question 6

Extraoral images are recommended for evaluating:
a. large areas of the jaw.
b. incipient dental caries.
c. early periodontal changes.
d. gingival recession.

Accepted Answer

Correct Answer:
a. large areas of the jaw.
Rationale:
Extraoral images are useful when evaluating large areas of the skull or jaw but have never been recommended for detection of subtle changes, such as dental caries or early periodontal changes.

Question 7

The collimator limits the diameter of the x-ray beam to:
a. 2 inches.
b. 3.25 inches.
c. 3.50 inches.
d. 4 inches.

Accepted Answer

Correct Answer:
a. 2 inches.
Rationale:
The collimator is a lead disc with a small central opening. It's located in the position indicator device (PID) and is used to limit the diameter of the collimated x-ray beam to a circular 2-inch diameter at the

Question 8

Which best describes the focal trough in panoramic imaging?
a. Imaginary plane that passes through the top of the ear canal
b. Imaginary line that divides the patient's face into right and left sides
c. Area of ideal focus
d. Area that can be shown du

Accepted Answer

Correct Answer:
c. Area of ideal focus
Rationale:
The focal trough is an area of ideal focus for producing clear and well-defined panoramic images. The Frankfort plane is an imaginary plane that passes through the top of the ear canal and the bottom of

Question 9

A bitewing film shows the _______ of both the __________ and __________.
a. entire tooth; maxilla; mandible
b. roots; right; left
c. crowns; maxilla; mandible
d. entire tooth; posterior; anterior

Accepted Answer

Correct Answer:
c. crowns; maxilla; mandible
Rationale:
A bitewing film shows the crowns of both the maxilla and the mandible.

Question 10

Dental personnel should strive to curb the occupational dose of radiation to:
a. 5.0 rems/year.
b. 0.1 rems/year.
c. 0.0 rems/year.
d. 2.5 rems/year.

Accepted Answer

Correct Answer:
c. 0.0 rems/year.
Rationale:
Dental personnel should strive to maintain an occupational radiation exposure of zero, which is easily accomplished by following a strict radiation protection protocol.

Question 11

The first step in preparing a radiography operatory is to:
a. seat the patient.
b. gather all necessary supplies.
c. identify surfaces to be disinfected or protected with barriers.
d. dispense the film or PSPs in a paper cup or disposable container.

Accepted Answer

Correct Answer:
c. identify surfaces to be disinfected or protected with barriers.
Rationale:
The first step in preparing an operatory is identifying which surfaces need to be disinfected and/or protected with barriers. Gathering necessary supplies is

Question 12

Intraoral digital sensors:
a. do not contact mucous membranes.
b. cannot withstand heat sterilization.
c. should be immersed in a high-level disinfectant.
d. can be covered with plastic wrap or foil barriers.

Accepted Answer

Correct Answer:
b. cannot withstand heat sterilization.
Rationale:
Intraoral digital sensors come into contact with mucous membranes but cannot withstand heat sterilization or immersion in a high-level disinfectant. The CDC recommends using an FDA-appr

Question 13

The quantity of x-rays produced is controlled by:
a. voltage.
b. kilovoltage.
c. kilovoltage peak.
d. milliamperage.

Accepted Answer

Correct Answer:
d. milliamperage.
Rationale:
Milliamperage controls the penetrating power of the x-ray beam by controlling the number of electrons produced in the x-ray tube and the number of x-rays produced. Higher milliampere settings produce a beam

Question 14

Which entity makes infection control recommendations for dental radiology?
a. Food and Drug Administration
b. Centers for Disease Control and Prevention
c. American Dental Association
d. American Roentgen Ray Society

Accepted Answer

CORRECT ANSWER:
b. Centers for Disease Control and Prevention

Question 15

Dental x-rays are which type of radiation?
a. Electromagnetic
b. Particle
c. Acoustic
d. Gravitational

Accepted Answer

Correct Answer:
a. Electromagnetic
Rationale:
X-rays are classified as electromagnetic radiation, along with visible light, radar, radio, and television waves.

Question 16

Radiation leakage is emitted if the x-ray tubehead has:
a. anode pitting.
b. a faulty seal.
c. loose bolts at the yolk.
d. high x-ray tube current (mA).

Accepted Answer

Correct Answer:
b. a faulty seal.
Rationale:
Leakage radiation is emitted if the tubehead has a faulty seal. Anode pitting and high x-ray tube currents produce tubehead failure. Loose bolts at the yolk cause tubehead drift.

Question 17

Which radiograph is prescribed for the evaluation of the skeletal structures of the face?
a. Periapical
b. Cephalometric
c. Bitewing
d. Occlusal

Accepted Answer

Correct Answer:
b. Cephalometric
Rationale:
The cephalometric radiograph reveals facial skeletal structure and is prescribed when a skeletal evaluation is of particular benefit.

Question 18

Which best describes the infection control protocol for digital sensors?
a. Most sensors can be gently misted with surface disinfectant.
b. Cleaning and disinfecting procedures vary according to the manufacturer.
c. Only use an indirect disinfectant ap

Accepted Answer

Correct Answer:
b. Cleaning and disinfecting procedures vary according to the manufacturer.
Rationale:
Sensors can be easily damaged if improperly handled; the cleaning and disinfecting protocol differs between manufacturers. Sensors should be disinfec

Question 19

Gloves are NOT worn in which step?
a. Place each exposed PSP in a paper cup.
b. Open the sealed envelope and drop the PSP into the black transfer box.
c. Remove operatory barriers, taking care not to touch the surfaces beneath.
d. Load the PSP plates

Accepted Answer

Correct Answer:
d. Load the PSP plates into the scanning device.
Rationale:
PSP plates can be safely handled and loaded into the scanning device with clean bare hands, after the plastic barrier envelopes have been removed. Gloves are worn to remove ope

Question 20

A periapical view extends beyond the apices of the tooth:
a. 0 to 1 mm.
b. 2 to 3 mm.
c. 5 to 6 mm.
d. 7 to 8 mm.

Accepted Answer

Correct Answer:
b. 2 to 3 mm.
Rationale:
Periapical radiographs show the entire tooth, from occlusal surface or incisal edge to 2 to 3 mm beyond the apex.

Question 21

After the lead apron is used, it should be:
a. sterilized.
b. folded and stored.
c. hung up or laid on a rounded bar.
d. recycle

Accepted Answer

Correct Answer:
c. hung up or laid on a rounded bar.
Rationale:
Once the lead apron has been used, it must be disinfected and hung up or laid on a rounded bar. The lead apron should never be folded, as it will crack, and permanent damage will make it i

Question 22

Which patient protection technique is implemented first?
a. Proper film processing
b. Proper prescribing of radiographs
c. A lead apron
d. A thyroid collar

Accepted Answer

Correct Answer:
b. Proper prescribing of radiographs
Rationale:
Proper prescribing of radiographs is the first patient protection technique, because it limits the patient's exposure to radiation. The professional judgment of the dentist is used to dete

Question 23

Which skull radiograph shows the frontal sinuses, ethmoid sinuses, orbits, and nasal cavities?
a. Lateral cephalometric projection
b. Temporomandibular joint projection
c. Posteroanterior projection
d. Lateral jaw projection

Accepted Answer

Correct Answer:
c. Posteroanterior projection
Rationale:
The posteroanterior projection shows the frontal sinuses, ethmoid sinuses, orbits, and nasal cavities. This projection is used to evaluate facial growth and development, trauma, disease, and deve

Question 24

The effect of radiation exposure is:
a. reversible.
b. cumulative.
c. regenerative.
d. temporary.

Accepted Answer

Correct Answer:
b. cumulative.
Rationale:
Radiation exposure has a cumulative effect over a lifetime; some tissues can repair some damage, but they never return to their original state.

Question 25

Which produces a three-dimensional radiographic image?
a. Panoramic imaging
b. Computed tomography
c. Cone beam computed tomography
d. Computed axial tomography

Accepted Answer

Correct Answer:
c. Cone beam computed tomography
Rationale:
Cone beam computed tomography produces a three-dimensional (3D) radiographic image. Panoramic imaging and computed tomography, also referred to as computed axial tomography, produce two-dimens

Question 26

Which is the best surface disinfectant for the radiology operatory?
a. Iodophors
b. Ethyl alcohol
c. Sodium hypochlorite
d. Quaternary ammonium compounds

Accepted Answer

Correct Answer:
a. Iodophors
Rationale:
Iodophors are approved for surface disinfection in the radiology operatory as a hospital grade EPA-registered disinfectant with tuberculocidal action. Ethyl alcohol is not effective in the presence of blood and s

Question 27

Skull radiography is most commonly used in:
a. periodontics and endodontics.
b. oral surgery and orthodontics.
c. pediatric dentistry and maxillofacial pathology.
d. prosthodontics and dental anesthesiology.

Accepted Answer

Correct Answer:
b. oral surgery and orthodontics.
Rationale:
Skull radiography is used most often in oral surgery and orthodontics.

Question 28

The patient's dental radiographs are the legal property of the:
a. patient.
b. court.
c. dentist.
d. state.

Accepted Answer

Correct Answer:
c. dentist.
Rationale:
The dentist legally owns the patient's dental records, including radiographs; patients may request a copy of their radiographs from the dentist.

Question 29

Which film provides a wide view of the maxilla and mandible?
a. Bitewing
b. Periapical
c. Panoramic
d. Occlusal

Accepted Answer

Correct Answer:
c. Panoramic
Rationale:
A panoramic film is an extraoral radiograph designed to provide a wide view of the maxilla and mandible on a single film.

Question 30

The lead apron is:
a. recommended for intraoral films.
b. not recommended for extraoral films.
c. an option; use is not mandated by any state or federal law.
d. used to protect the thyroid gland.

Accepted Answer

Correct Answer:
a. recommended for intraoral films.
Rationale:
The lead apron is a flexible shield placed over the patient's chest and lap to protect the reproductive and blood-forming tissues from scatter radiation; the lead prevents the radiation fro

Question 31

Carious lesions appear ______________ on processed radiographs.
a. radiopaque
b. radiolucent
c. geometric
d. poorly defined

Accepted Answer

Correct Answer:
b. radiolucent
Rationale:
Dental caries appear radiolucent rather than radiopaque, geometric, or poorly defined. As demineralization and destruction of the hard tooth structures take place, the tooth density in the area of the lesion al

Question 32

A barrier is preferred over disinfectant for which surface in the radiography operatory?
a. Footrest
b. Lead apron
c. Electrical switch
d. Operator chair

Accepted Answer

Correct Answer:
c. Electrical switch
Rationale:
Surface barriers are preferred over disinfectant for electrical switches to prevent an electrical short. The footrest and operator chair may be disinfected with a high-level surface disinfectant or protec

Question 33

On a radiograph, which is most radiolucent?
a. Bone
b. Enamel
c. Amalgam
d. Pulp

Accepted Answer

Correct Answer:
d. Pulp
Rationale:
Radiation passes easily through dental pulp, making it radiolucent (dark) in a radiographic image. Bone, enamel, and amalgam restorations appear radiopaque (white or light gray).

Question 34

Which is (are) always worn when exposing images?
a. Protective clothing
b. Protective clothing and gloves
c. Protective clothing, gloves, and eyewear
d. Protective clothing, gloves, eyewear, and a mask

Accepted Answer

Correct Answer:
b. Protective clothing and gloves
Rationale:
Protective clothing and gloves are always worn when exposing images. A mask and eyewear are indicated when there is likelihood that blood or body fluids may spatter. A mask is also worn if th

Question 35

Which change will produce images that are more dense (darker)?
a. Decreasing the kilovoltage peak
b. Decreasing the milliamperage
c. Decreasing the exposure time
d. Decreasing the source-to-film distance

Accepted Answer

Correct Answer:
d. Decreasing the source-to-film distance
Rationale:
As x-rays travel away from their source of origin, the intensity of the beam lessens. Unless a corresponding change is made in one of the exposure factors (kilovoltage peak, milliampe

Question 36

Which is an extension of the x-ray tubehead used to direct the x-ray beam?
a. Aluminum disk
b. Position indicating device (PID)
c. Collimator
d. Filter

Accepted Answer

Correct Answer:
b. Position indicating device (PID)
Rationale:
The PID is an open-ended lead-lined cylinder extending from the opening of the metal housing of the tubehead; it aims and shapes the x-ray beam (also called the cone).

Question 37

The thyroid collar is:
a. not recommended for children.
b. required for all extraoral films.
c. a separate shield or part of the lead apron.
d. fastened securely over the lap area.

Accepted Answer

Correct Answer:
c. a separate shield or part of the lead apron.
Rationale:
The thyroid collar is designed as a separate shield or is part of the lead apron. A thyroid collar is especially important for pediatric patients because the thyroid gland in ch

Question 38

Which is true of computed tomography (CT)?
a. CT images are three-dimensional (3D).
b. CT images are digital and film-free.
c. CT imaging requires no x-radiation.
d. CT imaging is used primarily in pediatric dentistry.

Accepted Answer

Correct Answer:
b. CT images are digital and film-free.
Rationale:
CT images are digital and require no film; however, x-radiation is used as the energy source. CT images are two-dimensional (2D) and are used primarily in dentistry for diagnosing lesio

Question 39

Which statement is true?
a. The dentist is usually the person who actually exposes and processes radiographic film.
b. The dentist is ultimately responsible for the diagnostic quality of all radiographs exposed in his or her office.
c. An error in film

Accepted Answer

Correct Answer:
b. The dentist is ultimately responsible for the diagnostic quality of all radiographs exposed in his or her office.
Rationale:
Regardless of who exposes and processes the film, the dentist is responsible for the diagnostic quality of a

Question 40

If a lead apron is folded after being used, it will __________ and __________.
a. leak; mold
b. crack; become ineffective
c. magnetize; disrupt a pacemaker
d. crease; remain effective

Accepted Answer

Correct Answer:
b. crack; become ineffective
Rationale:
Lead aprons and thyroid collars must not be folded when stored. Folding eventually cracks the lead and allows radiation leakage.

Question 41

PSPs should never be placed in a:
a. scanner.
b. paper cup.
c. black transfer box.
d. laboratory coat pocket.

Accepted Answer

Correct Answer:
d. laboratory coat pocket.
Rationale:
Never place PSPs or film in a laboratory coat pocket or uniform pocket.

Question 42

Which type of radiation is most useful to the dental patient?
a. Primary
b. Secondary
c. Tertiary
d. Scatter

Accepted Answer

Correct Answer:
a. Primary
Rationale:
Primary radiation, emitted from the target of the x-ray tube, makes-up the useful beam. Secondary radiation is less penetrating and useless—it destroys the diagnostic quality of the film. Scatter radiation is a for

Question 43

Which exposure is particularly beneficial to the orthodontic patient?
a. FMS
b. Panoramic
c. Cephalometric
d. Bitewing

Accepted Answer

Correct Answer:
c. Cephalometric
Rationale:
The orthodontist uses the lateral cephalometric projection for diagnosis because it reveals the bones of the face and skull in addition to the soft tissue profile of the face.

Question 44

dental radiographs must be:
a. licensed.
b. over the age of 18.
c. trained and certified.
d. enrolled in a radiology course.

Accepted Answer

Correct Answer:
c. trained and certified.
Rationale:
Dental assistants who take radiographs must be trained and certified, according to the Consumer Radiation Health and Safety Act. Certification requirements vary from state to state.

Question 45

The patient bites the entire film for which exposure?
a. Bitewing
b. Occlusal
c. Periapical
d. Panoramic

Accepted Answer

Correct Answer:
b. Occlusal
Rationale:
The patient occludes or bites on the entire large intraoral film for an occlusal exposure.
According to the Consumer-Patient Radiation Health and Safety Act, individuals who take

Question 46

To retrieve extra supplies from an operatory drawer during a radiographic procedure:
a. open the drawer carefully and touch only the needed items to avoid cross-contamination.
b. remove one glove and open the drawer with the ungloved hand to retrieve th

Accepted Answer

Correct Answer:
d. don overgloves before touching the drawer or its contents.
Rationale:
To retrieve additional supplies during a radiographic procedure, don overgloves or ask for assistance. Opening the drawer and touching its contents with contaminat

Question 47

When x-rays contact matter, which occurs most frequently?
a. No interaction
b. Photoelectric effect
c. Compton scatter
d. Coherent scatter

Accepted Answer

Correct Answer:
c. Compton scatter
Rationale:
Most interactions (62%) between x-rays and matter result in compton scatter, in which the incoming photon hits and knocks an outer shell electron from orbit.

Question 48

Treating a patient without proper radiographs is a breach of:
a. ALARA.
b. confidentiality.
c. MPD.
d. standard of care.

Accepted Answer

Correct Answer:
d. standard of care.
Rationale:
In most cases, a lack of radiographs compromises the patient's diagnosis and treatment. The use of dental radiographs is now the accepted standard of care.

Question 49

_____ digital imaging involves digitizing an existing x-ray film using desktop scanners. Indirect digital imaging is _____ to direct digital imaging.
a. Indirect; inferior
b. Direct; inferior
c. Indirect; superior
d. Direct; superior

Accepted Answer

Correct Answer:
a. Indirect; inferior
Rationale:
Indirect digital imaging occurs when an existing radiograph is scanned and converted into a digital form. This method does not provide the same quality as would direct imaging.

Question 50

Rules of radiation protection for the operator include all except:
a. never stand in the direct line of the primary beam.
b. always stand behind a lead barrier or a proper thickness of drywall.
c. never stand closer than 3 feet from the x-ray unit duri

Accepted Answer

Correct Answer:
c. never stand closer than 3 feet from the x-ray unit during an exposure.
Rationale:
Distance recommendations indicate that the radiographer must stand at least 6 feet away from the x-ray tubehead during x-ray exposure or a protective b

Question 51

The shorter the wavelength of the x-ray, the:
a. greater its energy.
b. higher its amplitude.
c. weaker its energy.
d. lower its amplitude.

Accepted Answer

Correct Answer:
a. greater its energy.
Rationale:
The shorter the wavelength of an x-ray, the greater its energy. High energy short wavelengths penetrate matter more easily than longer wavelengths—a feature especially useful in dentistry.

Question 52

Primary radiation is:
a. often referred to as the useful beam.
b. less penetrating than secondary radiation.
c. created when the central ray interacts with matter.
d. deflected in all directions of the dental operatory.

Accepted Answer

Correct Answer:
a. often referred to as the useful beam.
Rationale:
Primary radiation is often referred to as the useful beam. Secondary radiation is less penetrating than primary radiation and is created when the primary beam contacts the patient's ti

Question 53

Which solution is best suited to preventing ghost images?
a. Ask the patient to remove all metal objects from head and neck before positioning.
b. Use a lead apron without a thyroid collar.
c. Instruct the patient to close the lips around the bite-bloc

Accepted Answer

Correct Answer:
a. Ask the patient to remove all metal objects from head and neck before positioning.
Rationale:
A “ghost” image results when metallic or radiodense objects such as eyeglasses, jewelry, removable partial dentures, orthodontic retainers,

Question 54

Which technique reveals the most accurate buccal/lingual position of impacted teeth?
a. Panoramic imaging
b. Cone beam computed tomography
c. Transcranial TMJ imaging
d. Posteroanterior projection

Accepted Answer

Correct Answer:
b. Cone beam computed tomography
Rationale:
Cone beam computed tomography (CBCT) enhances the diagnostic abilities of the dentist by accurately revealing the buccal/lingual position of impacted teeth.

RHS MC questions

Multiple Choice questions

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