Radiology

When the electrons strike the target, ____________________ are generated

99% heat and 1% x-rays

Infection-control guidelines are made by the:

CDC

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

Cephalometric

The person ultimately liable for what happens in the dental office is the:

Dentist

And exposed film left in the developer too long will

Appear similar to the way it would look if the solution were too hot

What color of light is produced when utilizing and intensifying screen that uses calcium tungstate a common type of phosphor?

Blue

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

Increase kVp

Dental film speed increases as a result of _______ in the size of silver halide crystals, which results in a _______in the amount of radiation used

Increase, decrease

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

Number of x-rays produced

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

Parent or relative of the patient

And advantage of digital x-rays is that they

Produce less radiation, require less equipment, are more sanitary

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?

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

What natural source of radiation provides the greatest amount of exposure per year?

Radon

Which type of cells or tissue is the most sensitive to radiation?

Reproductive

What is the purpose of aluminum filtration in the x-ray tube head

To remove the low energy, long wavelength x-rays

The x-ray was discovered in 1895 by

Wilhelm Conrad Roentgen.

The Consumer-Patient Radiation Health and Safety Act requires that

anyone taking radiographs be trained and certified.

Positioning instruments in digital radiography

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

Which of the following is the basic form of matter

atom

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

beam alignment devices such as the Rinn XCP instruments and positioning instruments such as the disposable polystyrene bite-block, EeZee-Grip, and EndoRay

Intraoral digital sensors come into contact with mucous membranes and ideally should be cleaned and heat-sterilized

between patients

Damage caused by ionizing x-radiation to genetic cells

can affect future generations.

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

cathode

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

clear

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

contrast

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

darkroom

The correct order of steps in manual film processing is

develop, rinse, fix, wash

One reason for a lighter than normal radiograph is the

developer solution is too weak

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

direct digital radiography

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

erythema

A latent image is an image that

exists on an exposed film before its developed

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

exposure time and mA

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

extension arm

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

fast film or digital imaging

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

focal spot

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)

intensifying screen

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

kilovolt setting

Faster film speed would be associated with _____ silver halide crystals, a _______ emulsion, and presence of special radiosensitive dyes

larger, thinner

Automatic film processing requires _____ than manual film processing does.

less equipment

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

light

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

muscle

A lead apron and a thyroid collar

must be used on all patients for all exposures

What is the main advantage of using a rectangular collimator over a circular one?

reduce patient exposure

Secondary radiation

refers to x-radiation that is created when the primary beam interacts with matter.

Key areas of __________ include consent, patient needs, and liability issues

risk management

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

sharpness

Chronic radiation exposure occurs when _____ doses of radiation are received over a _______ time period

small; long

Quality-control tests alert the user regarding:

the functional state of equipment and the quality of supplies.

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

the latent period.

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

4 feet

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

5

What is the maximum permissible dose of whole body radiation for persons occupationally exposed to radiation

5000 MREM, or 5REM per year

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

6

The uses of dental images include the detection of

Abnormalties in surrounding hard and soft tissues

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

Absorbs heat created by the production of x-rays

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

Evaluate the x-ray equipment and techniques

Extra oral film differs from intraoral film in that

Extra oral film is sensitive to specific color light

What is the difference between a speed film in the more recently developed F speed film?

F speed film has larger silver bromide crystals

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

Gelatin that suspends the emulsion

The function of the _________ filter in the x-ray tube is to ____________________.

aluminum; remove long wavelengths from the beam

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

quality

The term ____________ is used to describe areas that appear dark on the image; ___________ is the term used to describe areas that appear white or light gray.

radiolucent; radiopaque

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

reduce film fogging

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

reducing the number of exposures, keeping exposures levels as low as possible, minimizing retakes.

Dental imaging

refers to film-based images, refers to digitally produced images, detects conditions that might otherwise remain undetected

Thermionic emission refers to the

release of electrons from the tungsten filament

The lead collimator is used to

restrict the size and shape of the primary beam

In dentistry, the __________ the wavelengths of the x-rays, the greater their energy and their usefulness. straighter

shorter

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

should be autoclaved

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.

toward; occlusal or incisal

The surfaces in the radiography operatory that are likely to become contaminated when exposing x-rays are the tubehead and PID, the lead apron and chair controls, and the counter surfaces and exposure button.

true

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

2

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

2.50 mm

Which size of film should be used for in occlusal x-ray

4

The film layer that contains the Latent image is the

Emulsion

_____ hardens the film emulsion during film processing.

Fixer

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

Front

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

Silicon

Fixer cutoff will result in a _____ border.

Straight black.

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

Sudden temperature change between developer and water bath

Exposure to radiation

no matter how small, has the potential to cause harmful biological changes

Dental radiographs are:

original, part of the patient's record, never to be surrendered under any circumstances.

What is the fuzzy or blurred area that surrounds an x-ray image

penumbra

Which particles compose the nucleus of an atom?

protons and neutrons

The life of the processing solutions is affected by

the time elapsed since last change

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

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

What is the name given to the protective flexible lead shield that is placed over the neck region during x-ray exposure?

thyroid collar

A stepwedge radiograph is used to:

verify developer solution strength on a day-to-day basis

The heart of the x-ray generating system is the

x-ray tube.

What is the positive electrode that acts as the target for the electrons in the x-ray tube called

Anode

Which of the following tissues has the highest radiation sensitivity?

Bone marrow

Intensifying screens are used to

Decrease the amount of radiation used to expose extra oral films

Which of the following statements about duplicating film is not correct

Duplicating film is not intended to be used intraorally.

A radiograph used to show the crowns of both arches on a single film and commonly used to diagnose cavities is called

bite-wing

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

both sight of patients and sight of personnel.

An example of cumulative radiation exposure is

cataracts, leukemia, and cancer

The major source of cross-contamination during radiographic procedures is the

exposed film packet

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

low contrast

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

metal restorations.

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

milliampere seconds