DA23.3H- Radiology
scatter radiation
A form of secondary radiation that occurs when an x-ray beam has been deflected from its path by interaction with matter
what type of holder can use for bisecting technique
ALL OF THE ABOVE ( DISPOSBLE BITE BLOCK ,HEMOSTATE, SNAPERRAY)
Weak radiation leaving the tube during exposure is prevented by the use of a/an:
Aluminum Filter
Which option below, best describes an ion?
An atom that has lost electrons
What is the negatively charged particle that is responisble for producing dental radiographs?
Electron
Foreshortening of the maxillary radiographic image results from:
Excessive vertical angulation
Quality control tests are used to monitor and maintain all the following except:
Exposure Technique
All extraoral and intraoral radiographs can be taken with the same type of x-ray unit.
False
Radiation leaks are always detectable by either taste or smell
False
The advantages of the bisecting technique outweigh the disadvantages
False
All x-ray machines made after 1974 must abide by ___________ guidelines that regulates performance standards.
Federal
What is the speed of electrons through a circuit referred to as?
Kilovoltage
What is the term for a pattern of stored energy on the exposed film that cannot be visibly seen?
Latent image
What radiation protection would be used on the patient?
Lead apron
What component of the x-ray tube head restricts the size of the x-ray beam?
Lead collimator
What component of a film packed is included to reduced back scatter that can cause film fogging?
Lead foil sheet
The cathode in the_________________________ terminal.
Negative
a full mouth survey for a x-ray dentureless patient would include what
PA NO BITE WINGS
The beam of radiation which is responsible for exposing the xray film is the:
Primary Radiation
general radiation
Produced when an electron hits the nucleus of a tungsten atom or passes very close to the nucleus of a tungsten atom.
Sensors that cannot be sterilized
Require complete coverage with disposable plastic sleeves for each patient
The following substance found in the emulsion of a film is responsible for an x-ray image:
Silver halide (nitrate) crystals
What is the recommended film size for the bisecting technique?
Size 2
The panoramic image is the preferred image for the detection of caries and periodontal disease. The panoramic image is preferred for the evaluation of eruption patterns, growth, and development.
The first statement is false, the second is true
Your patient has asked why you prefer digital imaging to film. Which of the following reasons would you tell her?
The image appears instantaneously for both of us to view.
Film speed is determined by:
The size of the silver halide crystals
What is the purpose of the fixer?
To stop the action of the developer
The amount of electrons passing through a cathode filament is determined by the:
ampere
what is an Ion
an atom that has lost electrons
Disadvantages of the bisecting technique include:
angulation problems and image distortion
When exposing periapical radiographs with the bisecting technique, always begin with the:
anterior teeth
character radiation
arises from the electronic transition in an excited atom.
what xray will we take to see the interproximal decay
bite wing
The material responsible for giving support and stiffness to the x-ray film is called:
cellulose acetate
what is the material that give the film stiffness and support
cellulose acetate
An exaggerated smile line is seen on the dental image if the patient's
chin is tipped down
A reverse smile line is seen on the image if the patient's
chin is tipped up
what part of the xray unit restricts the beam to 2.75 inches at the end of the cone
collimator
The overall blackness of the film is termed the:
density
When looking at amount of radiation needed for digital vs film x-ray, how do they differ?
digital requires less radiation than film to produce an image
Too little vertical angulation result in images that are:
elongated
an inccorect vertical angle to the PID causes what
elongation
The latent period in radiation biology is the period of time between:
exposure to x-radiation and clinical symptoms
weak radiation leaving the tube during exposer is prevented by the use of
filter
Too much vertical angulation results in images that are:
foreshortened
Radiation injuries that are not seen in the person irradiated but that occur in the future generations are temed:
genetic effects
Each panoramic unit has a(n) _______________ that is used to align the patient's teeth as accurately as possible
head positioner
When mA is decreased the exposure time is:
increased
Dental receptors placed inside the mouth are termed:
intraoral
In dental radiography the quality of the beam is conducted by:
kVp
what controls the speed of electrons going through a circut
kVp
is the cathode negative or positive
negative
Incorrect horizontal angulation results in images that are:
overlapped
incorrect horizontal angulation causes what
overlapping
the beam of radiation that is responsible for exposing the xray film
primary or direct
The coin test is conducted to determine:
proper safelighting
The function of the collimator used in the panoramic x-ray machine is to____________
restrict the size and shape of the x-ray beam
The bisecting technique is based on the:
rule of isometry
Radiation produced with high kilovoltage results in:
short wave lengths
what is the name of that stuff in the imusion of the film that is responsible for the x-ray image
silver halide crystals
mounting an upper bicuspid what would be a good landmark to look for
sinuses
what is the most commom film size
size 2
Which of the following is most susceptible to ionizing radiation?
small lymphocyte
what part of the intraoral camera goes inside the mouth
the wand
To avoid a lead apron artifact on a panoramic radiograph
use a lead apron without a thyroid collar, and place the lead apron low around the neck of the patient so that it does not block the x-ray beam.
which part of the digital camera show the image display prior to taking the image
view finder
what is the first the firt thing you should do after removing
wipe the saliva
Primary radiation
x-ray beam after it leaves the x-ray tube and before it reaches the object
Which of the following described the relationship of the central ray to the receptor in the paralleling technique?
90 degrees to the film and long axis of the tooth
Which describes the proper direction of the central ray in the bisecting technique?
90 degrees to the imaginary bisector
Film emulsion includes:
- Silver bromide - Silver iodide - Gelatin
The identification dot on the intraoral film is significant because:
- The dot indicates the patient's right or left - The dot determines film orientation - The dot is important in film mounting
Advantages of panoramic imaging include which of the following:
- The entire maxilla and mandible are seen on one image - It is easy and quick to learn how to expose a panoramic image. - Patients prefer panoramic images and are exposed to less radiation
Which of the following is an indication for the bisecting technique:
- When the patient states that is too painful to bite down on a bite block - When the patient has a shallow patient - When a rubber dam is placed
Digital imagin systems can be used for which images?
- bite-wing - panoramic - cephalometric
Which of the following is the recommended angulation for properly capturing a periapical film of the mandibular premolars?
-10 to -15
how many xrays are in a full mouth series
18
exposure to a dentureless patient cn be reduced to how much
25%
An occlusal receptor (size ____) may be used for some extraoral images.
4
The side of the patient's head is positioned adjacent to the cassette for what type of x-ray
Cephalometric
why is radiation considered harmful?
Cumulative
What is used to determine film orientation?
Identification dot
In the bisecting technique, the radiographer must visualize the plane that divides in half the angle formed by the receptor and the long axis of the tooth. This plane is termed the:
Imaginary bisector
Besides Gamma rays, what additional radiation wave from the EMR spectrum is considered harmful to tissue due to its wavelength?
Ultra-Violet
After removing an exposed film from the patient's mouth, the first thing you should do is:
Wipe saliva from the film
secondary radiation
X-radiation that is created when the primary beam interacts with matter
Which beam alignment device includes bite blocks, aiming rings, and indicator arms?
XCP