DANB proficiency 3
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
When the electrons strike the target, ____________________ are generated.
99% heat and 1% x-rays
Which of the following is an extraoral film that is placed outside the mouth during dental x-ray exposure procedures?
Cephalometric
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
Which of the following is the basic form of matter?
An atom
The council that determines the radiation effects and levels tolerable for humans is the
National Council on Radiation Protection and Measurements
If you change the exposure time of the x-ray unit, what is affected?
Number of x-rays produced
The dentist who is credited making the first dental radiograph in 1895 is
Otto Walkhoff
Who should hold the film in a patient's mouth if the patient is unable to do so?
Parent or relative of the patient
Which of the following terms is used to describe the energy or penetrating ability of the x-ray beam in dental radiography?
Quality
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
Which of the following statements about duplicating film is not correct?
The emulsion side of the film appears shiny
Which of the following statements is true concerning the structure of the atom?
The orbital path of an electron around the nucleus is called an electron shell
The x-ray was discovered in 1895 by
Wilhelm Conrad Roentgen
When film emulsion interacts with x-rays, the result is
a latent image
The uses of dental images include the detection of
abnormalities in surrounding hard and soft tissues
The function of the _________ filter in the x-ray tube is to ____________________.
aluminum; remove long wavelengths from the beam
Positioning instruments in digital radiography
assist in film placement and keep the patient's fingers from being exposed
A step-down transformer is necessary within the x-ray circuitry to
boil off electrons from the filament.
Which of the following tissues has the highest radiation sensitivity?
bone marrow
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
All the following are true of electromagnetic radiation except they
contain radioactive substances such as uranium
The range of shades of gray between black and white on an image is called
contrast.
When developer solution in an automatic processor is warmer than 83 F, the processed film will appear
dark or black
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
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
Clear spots on a processed film can be caused by
fixer contacts film prior to processing
The location where x-rays are produced in the x-ray tube is called the
focal spot
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 dentist says that the image has too much contrast; she would like to see more gray values. What adjustment would you make?
increase kVp
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
All the following are true statements about digitizing film-based radiographic images except
it duplicates in the same detail as the original film.
The penetrating power of the x-ray beam is controlled by the settings on the
kilovolt setting
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
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
Which of the following statements is true regarding federal and state regulations on the use of dental x-ray equipment?
most states have laws that require inspections of dental x-ray equipment on a regular basis.
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
Failure to obtain informed consent from a patient prior to exposure of dental radiographs can lead to charges of
negligence
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
Green-sensitive extraoral film is used with cassettes that have which type of intensifying screen?
rare earth
The purpose of the lead foil in the dental film packet is to
reduce film fogging.
Secondary radiation
refers to x-radiation that is created when the primary beam interacts with matter.
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
Digital radiography requires less radiation than traditional radiography because the
sensor is more sensitive to x-ray energy
How well the image reproduces fine detail or distinct outlines of an object is called
sharpness
In dentistry, the __________ the wavelengths of the x-rays, the greater their energy and their usefulness.
shorter
All the following are true statements about phosphor storage plate (PSP) imaging system imaging plates except they
should be autoclaved.
The charge-coupled device (CCD) in direct digital imaging sensors is made of
silicon
The sharpness of a radiographic image can be improved by
smaller film crystal size
Faster film speed would be associated with _____ silver halide crystals, a _______ emulsion, and presence of special radiosensitive dyes.
smaller;thinner
When the master switch is on
the electron cloud is created around the tungsten filament
The time lapse from x-ray exposure until noticeable damage occurs is known as
the latent period
The most commonly used film size for adult intraoral dentistry is size
#2
What happens when the exposure button is engaged?
- The high-voltage circuit is activated. - Kilovolts drive the electrons to the target. - Electrons slam against the target producing the x-ray.
Primary radiation is
- also called the useful beam. - the beam of x-rays that comes from the target.
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. - positioning instruments such as the disposable polystyrene bite-block, EeZee-Grip, and EndoRay.
An example of cumulative radiation exposure is
- cataracts. - leukemia. - cancer.
When in storage, the lead apron should be
- hung - draped over a bar
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. - minimizing retakes. - keeping exposures levels as low as possible.
Dental imaging
- refers to film-based images. - refers to digitally produced images. - detects conditions that might otherwise remain undetected.
Because the entire x-ray area is considered a radiation hazard area, a radiation hazard sign must be posted in
- sight of patients. - sight of personnel.
The life of the processing solutions is affected by
- the number of films processed. - the time elapsed since last change. - the size of films processed.
An exposure time of 1/4 second is equal to _____ impulse(s).
15
How much filtration is federally required for a dental x-ray machine operating over 70 kVp?
2.50 mm
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
The ideal time and temperature for manual developing is
5 minutes at 68 F
If the operator's film badge indicates an exposure to small amounts of radiation, what should be done?
Evaluate the x-ray equipment and techniques
_____ hardens the film emulsion during film processing.
Fixing
The silver halide crystals are located within which of the following layers of the radiographic film?
Gelatin that suspends the emulsion
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
The _____________ is the space on the tongue side within the upper and lower dental arches.
oral cavity proper
Which of the following is the name for the primary kind of radiation produced in the dental x-ray tubehead?
particulate radiation
The fuzzy or blurred area around an image is called _____________. It can be reduced by _______________.
penumbra; limiting movement
The Consumer-Patient Radiation Health and Safety Act is a federal law that requires all
persons who use x-rays to take dental images to be properly trained and certified
The ________ is the area between the two ridges running from under the nose to the midline of the upper lip.
philtrum
When loading an extraoral film into the cassette prior to exposure, the
procedure must be done in the darkroom
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.
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 cartilaginous projection anterior to the external opening of the ear is called the
tragus
The heart of the x-ray generating system is the
x-ray tube