DANB

The uses of dental images include the detection of

1. incipient occlusal lesions.

2. abnormalities in surrounding hard and soft tissues.

3. periodontal probing depths.

4. percussion sensitivity as part of endodontic evaluation.

B

Exposure to radiationn

A. no matter how small, has the potential to cause harmful biologic changes.

B. has a threshold, below which exposure is entirely safe.

C. is safer when there is a single, large dose rather than a series of smaller doses.

D. from a dental x-ray machine does not involve particulate radiation and is completely safe.

A

The x-ray was discovered in 1895 by

1. John Greenwood.

2. Wilhelm Conrad Roentgen.

3. Edmund Kells.

4. G.V. Black.

B

The dentist who is credited making the first dental radiograph in 1895 is

1. Wilhelm Conrad Roentgen.

2. Otto Walkhoff.

3. John Greenwood.

4. G.V. Black.

B

Which of the following is the basic form of matter?

1. A proton

2. A solid

3. An atom

4. A photon

C

Which of the following statements is true concerning the structure of the atom?

1. The nucleus contains protons and electrons.

2. Electrons have no weight or mass.

3. The orbital path of an electron around the nucleus is called an electron shell.

4. Electrons are unstable in their orbits and shift freely.

C

In dentistry, the_______the wavelengths of the x-rays, the greater their energy and their

usefulness.

1. shorter

2. longer

3. more ionized

4. straighter

A

The component of the x-ray machine that functions in positioning the tubehead is the

1. kilovoltage selector.

2. control panel.

3. extension arm.

4. cathode.

C

The heart of the x-ray generating system is the

1. x-ray tube.

2. insulating oil.

3. transformer.

4. position indicator device.

A

All of the following structures will appear radiolucent on dental x-ray film except

1. metal restorations.

2. soft tissue.

3. tooth decay.

4. dental pulp.

A

The term________ Is used to describe areas that appear dark on the image; _______ term used to describe areas that appear white or light gray.

1. radiopaque; radiolucent

2. radiolucent; radiopaque

3. density; contrast

4. contrast; density

B

The range of shades of gray between black and white on an image is called

1. contrast.

2. density.

3. sharpness.

4. focus point.

A

The degree of density or blackness on an image is controlled by the

1. low-voltage circuit.

2. kilovoltage.

3. milliampere seconds.

4. position indicator device.

C

The sharpness of a radiographic image can be improved by

1. a larger focal spot size.

2. faster speed film.

3. smaller film crystal size.

4. movement of the patient.

C

Damage caused by ionizing x-radiation to genetic cells

1. affects only the person being exposed.

2. can affect future generations.

3. affects only the dental assistant.

4. affects the cells of the eye, skin, and oral mucosa.

B

Damage caused by ionizing x-radiation to genetic cells

1. affects only the person being exposed.

2. can affect future generations.

3. affects only the dental assistant.

4. affects the cells of the eye, skin, and oral mucosa.

B

Which of the following tissues has the highest radiation sensitivity?

1. Bone marrow

2. Salivary gland

3. Kidney

4. Muscle tissue

A

A lead apron and a thyroid collar a.

1. are used for a full-mouth series of films but are not necessary for single periapical films.

2. must be used on all patients for all exposures.

3. are required for pediatric patients but is optional for adults.

4. are mandated only for pregnant women.

B

The Guidelines for Prescribing Dental Radiographs issued by the American Dental Association and the FDA recommend which of the following dental imaging procedures for a pregnant patient?

1. Do not take images of a pregnant patient.

2. Radiographic imaging procedures do not need to be altered because of pregnancy.

3. Take images only after the first trimester.

B

One of the rules of radiation protection is never stand closer than _____ feet from the x-ray unit during an exposure unless you are behind a barrier.

a. 2

b. 6

C. 10

d. 15

B

The term image receptor refers to

1. either a digital imaging sensor or to film.

2. a digital imaging sensor only, not film.

3. film only, not a digital imaging sensor.

4. neither a digital imaging sensor nor film.

A

All of the following are true of electromagnetic radiation except they

1. are composed of photons that travel through space in waveforms.

2. contain radioactive substances such as uranium.

3. differ only by their wavelength.

4. travel in straight lines.

B

Which of the following is the name for the primary kind of radiation produced in the dental x-ray tubehead?

1. Characteristic radiation

2. Braking radiation

3. Particulate radiation

4. Electromagnetic radiation

B

The portion of the x-ray machine that supplies the electrons to produce x-rays is the

1. cathode.

2. anode.

3. control panel.

4. focusing cup.

A

If you change the exposure time of the x-ray unit, what is affected?

1. Energy of the beam

2. Wavelength of the x-rays

3. Number of x-rays produced

4. Penetrability of the x-rays

C

The penetrating power of the x-ray beam is controlled by the settings on the

1. exposure button.

2. kilovoltage setting.

3. milliamperage setting.

4. master switch.

B

A step-down transformer is necessary within the x-ray circuitry to

1. increase exposure time.

2. move electrons at a high speed to the target.

3. boil off electrons from the filament.

4. produce photons of sufficient energy to pass through the aluminum filter.

C

What is the purpose of the insulating oil that fills the x-ray machine housing and surrounds the x-ray tube?

1. Stabilizes and prevents drifting of the tubehead.

2. Insulates the tubehead from the sounds created by depressing the exposure button.

3. Lubricates the yoke of the tubehead so it does not squeak.

4. Absorbs heat created by the production of x-rays.

D

Thermionic emission refers to the

1. release of electrons from the tungsten filament.

2. ions formed in the x-ray tube by the loss of electrons.

3. change in filament resistance due to heating.

4. slamming of electrons against the target.

A

The lead collimator is used to a make the

1. primary beam more accurate.

2. restrict the size and shape of the primary beam.

3. remove long wavelengths.

4. stop production of the primary beam.

B

How much filtration is federally required for a dental x-ray machine operating over 70 kVp?

1. 2.75 mm

2. 2.50 mm

3. 2.25 mm

4. 0.5 mm

B

The function of the _______ filter in the x-ray tube is to _______

1. aluminum; remove long wavelengths from the beam

2. copper; remove long wavelengths from the beam

3. lead; restrict the size of the beam

4. aluminum; restrict the size of the beam

A

Primary radiation is

1. created when the x-rays contact the patient's tissues.

2. the beam of x-rays that comes from the target.

3. less penetrating than secondary radiation.

4. scatter radiation.

B

The fuzzy or blurred area around an image is called _________. It can be reduced by ___________

A. distortion; limiting movement

B. a penumbra; limiting movement

C. distortion; using fast film

D. a penumbra; using fast film

B

The council that determines the radiation effects and levels tolerable for humans is the

a. American Dental Association (Council on Radiation Safety).

b. American Dental Association (Council on Dental Materials).

c. National Council on Radiation Protection and Measurements (NCRP).

d. Occupational Safety and Health Administration (OSHA).

C

Because the entire x-ray area is considered a radiation hazard area, a radiation hazard sign must be posted in

a. sight of all patients and personnel.

b. the darkroom.

C. the doctor's private office.

d. the reception area.

A

The time-lapse from x-ray exposure until noticeable damage occurs is known as

a. acute radiation exposure.

b. chronic radiation exposure.

c. the latent period.

d. the cumulative period.

C

chronic radiation exposure occurs when _______ doses of radiation are received over a _______ time period.

a. large; short

b. large; long

C. small; short

d. small; long

D

Which of the following terms is used to describe the energy or penetrating ability of the x-ray beam in dental radiography?

a. Quantity

b. Quality

c. Collimation

d. Density

B

All of the following organs are more sensitive to radiation and are considered critical organs except

a. skin.

b. muscle.

c. thyroid gland.

d. lens of the eye.

B

The maximum permissible dose for an occupational worker for an individual 18 years of age or older is _____ rem/year

a. 3

b. 5

C. 1.25

d. 0.3

B

All of the following are true statements about film badges except

a. they should be worn at work only.

b. the badge is usually worn for 3 to 4 weeks before returning it for reading.

c. they should be worn when any form of x-ray is taken.

d. if an assistant follows all safety precautions; exposure should be near zero.

C

Who should hold the film in a patient's mouth if the patient is unable to do so?

a. Receptionist

b. Parent or relative of the patient

c. Assistant

d. Dentist

B

A patient is concerned with radiation exposure. You can assure him that your office uses the ALARA concept, which includes

a. routine time intervals between dental x-rays.

b. full sets of 18 images rather than panoramic images.

c. keeping exposures levels as low as possible.

d. taking yearly bitewing images.

C

One of the earliest signs of overexposure to x-rays may be

a. keratosis.

b. loss of hair.

c. erythema.

d. blindness.

C

If the operator's film badge indicates an exposure to small amounts of radiation, what should be done?

a. Consult a physician.

b. Ignore the report.

c. Evaluate the x-ray equipment and techniques.

d. Change the mA and kVp.

C

If a patient is small and petite, to get the same density radiograph, it is best to reduce the

a. exposure time.

b. mA.

c. kVp.

d. exposure time and mA.

D

An example of cumulative radiation exposure is

a. radiation sickness.

b. loss of hair.

c. cancer.

d. erythema of exposed skin.

C

The dentist says that the image has too much contrast; she would like to see more gray values. What adjustment would you make?

a. Increase mA.

b. Increase kVp.

c. Decrease kVp.

d. Decrease mA.

C

When in storage, the lead apron should be

a. laid out on the floor.

b. folded.

C. draped over a bar.

d. placed in a sweater box.

C

A good technique for reducing the radiation exposure to both patient and operator is the use of a.

a lead apron.

b. thinner films.

c. fast film or digital imaging.

d. an automatic processor.

C

A radiograph that has an overall gray appearance is generally preferred. This radiograph is said to have

a. high density.

b. low density.

c. high contrast.

d. low contrast.

D

How well the image reproduces fine detail or distinct outlines of an object is called

a. sharpness.

b. magnification.

c. density.

d. contrast.

A

The location where x-rays are produced in the x-ray tube is called the

a. focal spot.

b. filament.

c. window.

d. PID.

A

When the electrons strike the target, ___________ are generated.

a. 99% heat and 1% x-rays

b. 1% heat and 99% x-rays

C. 50% x-rays and 50% heat

d. only x-rays

A

What happens when the exposure button on a dental x-ray machine is pressed?

a. The low-voltage circuit is activated.

b. Kilovolt potential drives the photons to the target.

C. Electrons slam against the target of the anode producing the x-ray.

d. Electrons strike the cathode.

C

An exposure time of 1/4 second is equal to ______ impulses

a. 1/2

b. 15

C. 30

d. 2

B

When the master switch is on

a. x-rays are being produced.

b. the red emission light will illuminate.

c. the electron cloud is created around the tungsten filament.

d. photons travel from the cathode to the anode in the tubehead.

C

59. Dental film holders, used to position and hold the dental x-ray films in the patient's mouth, include

a. Rinn XCP-DS instruments.

b. Rinn XCP instruments.

C. film cassette.

d. position indicator device (PID.)

B

The silver halide crystals are located within which of the following layers of the radiographic film?

a. Acetate film base

b. Adhesive layer that attaches the emulsion to the film base

c. Gelatin that suspends the emulsion

d. Protective layer that protects the emulsion surface

C

F-speed dental x-ray film reduces radiation exposure to the patient by % compared with D-speed dental x-ray film.

a. 20

b. 40

C. 60

d. 80

C

The most commonly used film size for adult intraoral dentistry is size

a. #0

b. #2.

C. #3

d. #4.

B

Which of the following is an extraoral film that is placed outside the mouth during dental x-ray exposure procedures?

a. Periapical

b. Bite-wing

C. Cephalometric

d. Occlusal

C

A plastic or metal film cassette holds and protects the extraoral film. During exposure, the side of the cassette must face the patient is the _ side.

a. front

b. back

C. right

d. left

A

The device that intensifies or increases the effect of the radiation and decreases the amount of exposure time needed when exposing an extraoral radiograph is a(n)

a. screen film.

b. film cassette.

C. intensifying screen.

d. nonscreen film.

C

______ hardens the film emulsion during film processing.

a. Rinsing

b. Developing

C. Fixing

d. Washing

C

Automatic film processing requires _______ than manual film processing does.

a. more time

b. less equipment

c. more equipment

d. more space

B

Which of the following time and temperature errors will result in reticulation of the film emulsion?

a. Inadequate development time

b. Developer solution too hot

C. Sudden temperature change between developer and water bath

d. Inaccurate timer or thermometer

C

Fixer cutoff will result in a

a. straight white

b. straight black

c. curved white

d. curved black border.

B

The charge-coupled device (CCD) in direct digital imaging sensors is made of

a. silicon.

b. phosphor.

c. tungsten.

d. silver halide.

A

The category of digital imaging similar to faxes and video equipment that uses an intraoral sensor with a cord attached to the computer is

a. computed radiography programs.

b. indirect digital imaging.

c. direct digital imaging.

d. CAD/CAM.

C

All of the following are true statements about storage plates used with phosphor storage plate (PSP) imaging systems except that

a. they are made of phosphor.

b. the latent image will stay on the plate for hours.

C. they should not be exposed to light before scanning.

d. they utilize radio frequency transmission to transmit the image to the computer via radio waves.

D

All of the following are true statements about phosphor storage plate (PSP) imaging system imaging plates except they

a. need to be protected in the patient's mouth with barriers.

b. should be autoclaved®

c. require care not to scratch when handling.

d. are positioned in the mouth like dental film.

B

Positioning instruments in digital radiography

a. assist in film placement and keep the patient's fingers from being exposed.

b. are used with round, but not rectangular, position indicating device (PID).

C. are exactly the same x-ray film holders used in conventional techniques.

d. include the Rinn XCP system.

A

Faster film speed would be associated with ________ silver halide crystals, a _________ emulsion, and presence of special radiosensitive dyes.

a. larger; thicker

b. larger; thinner

C. smaller; thicker

d. smaller; thinner

A

The purpose of the lead foil in the dental film packet is to

a. provide stiffness to the film.

b. reduce film fogging.

C. absorb the primary beam.

d. make the packet more flexible and resilient.

B

When placing a dental film in the patient's mouth, the white side is placed _________ the dental x-ray tubehead, and the raised dot to the ________ surface.

a. toward; apical

b. toward; occlusal or incisal

C. away from; apical

d. away from; occlusal or incisal

B

Which of the following statements about duplicating film is not correct?

a. The emulsion is only on one side.

b. The emulsion side of the film appears shiny.

C. Duplicating film is not intended to be used intraorally.

d. Duplicating film is exposed by visible white light.

B

The safest place to store unopened boxes of dental film is in the

a. darkroom.

b. furnace room.

c. refrigerator.

d. treatment room.

A

80. The correct order of steps in manual film processing is

a. fix, rinse, develop, wash.

b. develop, rinse, fix, wash.

c. fix, wash, rinse, wash.

d. rinse, develop, fix, wash.

B

Solutions should have been changed in the processor 1 week ago. Continuing to use exhausted developer will result in films.

a. dark

b. light

c. white

d. clear

B

The recommended distance between the safelight and where the films are unwrapped is at least

a. 2 feet.

b. 4 feet.

c. 6 feet.

d. as close as possible.

B

The life of the automatic processer solutions is reduced rather than extended when

a. fewer films are being processed.

b. more time has elapsed since the last complete change of processing solutions.

c. the processor has an automatic replenisher.

d. manual replenishing has been accomplished on a daily basis.

B

When a film passes through fixer solutions before developing, the film will appear

a. white or light (clear).

b. completely black.

C. gray.

d. yellowish-brown.

A

One reason for a lighter than normal radiograph is the

a. developer solution is too weak.

b. developer solution is too warm.

c. fixer solution is too weak.

d. film was not properly rinsed.

A

When developer solution in an automatic processor is warmer than 83°F, the processed film will appear

a. dark or black.

b. gray.

c. clear.

d. light.

A

The ideal time and temperature for manual developing is

a. 45 seconds at 85°F.

b. 5 minutes at 65°C.

c. 5 minutes at 68°F.

d. 5 minutes at 60°F.

C

White or light (clear) spots on a processed film can be caused by

a. static electricity.

b. solutions are too warm.

c. fixer solution contacts film prior to processing.

d. drops of developer solution on a fixed film.

C

When loading an extraoral film into the cassette prior to exposure, the

a. film comes preloaded in the cassette.

b. procedure must be done in the darkroom.

C. film may be placed in the holder outside the darkroom.

d. film does not need an intensifying screen.

B

When film emulsion interacts with x-rays, the result is

a. a visible distortion.

b. a distorted light source.

c. a latent image.

d. a negative of the image.

C

Green-sensitive extraoral film is used with cassettes that have which type of intensifying screen?

a. Rare earth

b. Calcium tungstate

C. Charge-coupled device (CCD)

d. Phosphor storage plate (PSP)

A

Digital radiography requires less radiation than traditional radiography because the

a. exposure time is increased.

b. sensor is smaller.

C. sensor is more sensitive to x-ray energy.

d. sensor is attached to the computer.

C

Each of the following is true about digitizing film-based radiographic images except

a. the process is similar to other film duplication.

b. desktop scanners capture the light signal.

c. it duplicates with slightly less detail than the original film.

d. digitized film-based images cannot be enhanced by computer software.

D

Which of the following statements is true regarding federal and state regulations on the use of dental x-ray equipment?

a. All dental x-ray machines manufactured or sold in the United States after 1934 must meet federal regulations.

b. The use of dental x-ray equipment is regulated by federal but not state regulations.

c. The federal government requires x-ray machines to be registered and charges a fee for this registration.

d. Most states have laws that require inspections of dental x-ray equipment on a regular basis.

D

The Consumer-Patient Radiation Health and Safety Act is a federal law that requires all

a. persons who use x-rays to take dental images to be properly trained and certified.

b. persons who take dental x-rays to be registered with a national practitioner databank.

c. dental x-ray machines to be registered.

d. persons who expose dental x-rays to wear radiation safety badges.

A

Failure to obtain informed consent from a patient prior to exposure of dental radiographs can lead to charges of

a. informed consent.

b. disclosure.

c. respondeat superior.

d. negligence.

D

97. Dental images are the property of the

a. dentist.

b. patient.

c. patient's insurance company.

d. state board.

A

What should the dental assistant do if a patient refuses dental imaging?

a. Document in the patient's record the fact that he or she refused recommended dental imaging.

b. Tell the patient that the dentist doesn't mind working without dental images.

C. Attempt to take the dental images anyway.

d. Ask the patient to sign a waiver releasing the dentist from any liability for treating the patient without taking dental radiographs.

A

Quality assurance in the dental office is a way of ensuring that everything possible is being done to produce high-quality diagnostic images and includes quality control

a. tests and administration procedures.

b. of dental staff credentials.

c. during shipping from the manufacturer to the supplier.

d. of the manufacturing process.

A

According to the test for x-ray film freshness, the film is fresh and has been properly stored and handled when the processed film appears clean with a slight ________ tint

a. orange

b. green

c. blue

d. red

C