X-Ray Radiation Safety
What film speed types are used in intraoral dental radiographs?
D, E, F
Film size #1
anterior on adult and children
Secondary radiation is ___ useful radiation because it produces fog on the radiograph, ______ the diagnostic quality.
not;damaging
Film size #4
occlusal
Identification dot
on one corner of the film packet; small raised bump used to differentiate the left and right side
Film cassette
plastic or metal case that is used to hold the film and protect it from exposure to light
Film size #3
preformed bitewing; infrequently used
Kilovoltage
(kVp) highest voltage of x-ray tube used during an exposure
Dental x-ray machines general operate at ___ or ____ kVp.
70 or 90
Using proper exposure factors limits the amount of radiation exposure. A setting of ______ kVp keeps patients exposure to a minimum.
70 to 90
Film size #2
Adult size
ALARA Concept
As Low As Resonably Achievable; concept that all exposure to radiation must be kept to a minimum
Which film speed is the fastest and reduces exposure by how much?
F-speed; 20 to 60%
Lead apron should ________ when stored.
not be folded
Critical organs that are sensitive to radiation
Skin, Thyroid gland, Lens of the eye, Bone marrow
Example of positioning instruments
Snap ray and polystyrene bite blocks
Examples of radiolucent structures
air spaces, soft tissues, aabscesses, tooth decay, dental pulp
Beam alignment devices
assists in positioning of the PID in relation to the tooth and film or sensor
Film size #0
child size; younger than 3 yrs
Lead apron
covers the patient from the neck and extend over the lap area to protect the reproductive and blood-forming tissues from scatter radiation
Radiolucent
dark area
The ____ the film speed, the ____ radiation exposure to the patient.
faster; less
High contrast
fewer shades of gray
Radiation monitoring devices
film badge, pocket dosimeter (pen style), thermoluminescent device (TLD)
Thyroid collar
flexible lead shield that is placed securely around the patients neck to protect the thyroid from scatter radiation
Scatter Radiation
form of secondary radiation that occurs when an x-ray beam has been deflected from its path through interaction with matter. delfected in all directions including patients body, operatory
If the film packet is positioned in the mouth backward, what is produced on the film?
herringbone pattern
After the film has been processed, it becomes a ____ or _____.
image; radiograph
Types of film used in dentistry
intraoral, extraoral, duplicationg
Always stand behind a ________ or a ______ of drywall.
lead barrier; proper thickness
Dental x ray machines must be monitored for ________.
leakage radiation
A 90-kVp requires ____ exposure time and produces an image with _____ contrast.
less; low
A 70 kVp requires ____ exposure time and produces an image with ____ contrast.
longer; high
Primary Radiation
made up of the x-rays that come from the target of the x-ray tube. aka: useful beam or primary beam
Examples of radiopaque structures
metal restorations, tooth enamel, and dense areas of bone
A longer position indicator device (PID) is ______ in reducing exposure because of less divergence of the beam.
more effective
Low contrast
more shades of gray
Contrast
range of shades of gray to black to white
Panoramic film
shows panoramic view of the upper and lower jaws
Cephalometric film
shows the bony and soft tissue areas of the facial profile
If a lead barrier is not available, _______________.
stand at right angles to the beam
Film speed
the amount of radiation that is required to produce a radiograph of standard density
Primary beam
the most penetrating beam produced at the target of the anode
Tubehead
the part of the x-ray unit that contains the x-ray tube. the high voltage and low voltage transformers, and insulating oil
Duplicating film
used only in a darkroom setting and is never exposed to x-rays
Positioning instruments
used to position and hold dental x ray films or digital sensor in the patients mouth.
Latent image
when radiation interacts with the film and an image is produced but is not yet visible before processing
Radiopaque
white or light gray area
Secondary Radiation
x-radiation that is created when the primary beam interacts with matter. EX: when the x-rays of primary beam contact patient's tissues
The _______ is where x-rays are produced.
x-ray tube