X-ray license test review
What is a form of radiation protection for the patient?
A lead apron (not a lead shield)
How is collimation accomplished?
A lead washer
What happens when you sterilize?
All forms of microorganisms have been destroyed
What prevents weak radiation leaving the tube during exposure?
Aluminum filter
What is an ion?
An atom that has lost an electron
Why is radiating n considered harmful?
Because it is cumulative
What x-rays show the interproximal and are cavity detecting radiographs?
Bite wing x-rays
What is the negatively charged particle that is responsible for producing dental radiographs?
Electrons
The instrument from the XCP kit that allows the operator to align the PID at a right angle to the film and long axis of the tooth is?
Metal indicator rod
What is the cathode?
Negative terminal
What is radiopaque?
Shows white on the film
What substance is found in the emulsion of a film that is responsible for an x-ray?
Silver halide crystals
Identify the x-ray beam on picture
Study x-ray picture in notes
What causes cone cutting?
The center of the primary beam was not directed to the center of the film
What stops the developing agents?
The fixer
What is a good anatomical landmark to look for when mounting an upper bicuspid film?
The maxillary sinuses
What part of the x-ray machine produces the radiation?
The tube
What is density?
Thickness of an object being radiated
Why is radiating n considered harmful?
To prevent secondary radiation from fogging film
Why is a dental mask worn?
To protect the mucous membranes of the nose and mouth
What causes foreshortening?
Too high of a vertical angel?
What are considered radiation protection for the operator during patient exposure?
•The distance of 6-8 feet from tube •lead shield •double walled gypsum board
What films are extra-oral films?
•panorex •cephalometric •orthopantomaograph
How much radiation is reduced by using ultra speed film?
85%
What is contrast?
Difference between black, white, and shades of gray
The speed of electrons throughout a circuit is referred to as?
Kilovoltage
What is the occupational dose limits for radiation exposure in a calendar quarter (13 weeks) for the whole body?
1.25 REMS
What is the target distance for the paralleling technique?
12-16 inches
A full mouth x-ray for an edentulous patient would include?
14 periapicals and no bitewings
Exposure to an edentulous patient can be reduced by?
25%
At what age is the first radiographic survey on a child?
3 years old
What is the minimum allowable distance of the dark room safety light from the working counter top?
4 feet
What material is responsible for giving support and stiffness to the x-ray film?
Cellulose acetate
An extra-oral film that shows a lateral view of the skull is?
Cephalometric
What is distortion?
Changes in the shape or size of an object
What is reticulation?
Cracking of the film emulsion due to excessive heat during processing
When using ultra speed film would you increase or decrease the exposure time?
Decrease
What is radiolucent?
Degree of darkness on a film
Who can legally expose x-rays described by the "California law"?
Dental assistant who passes a board approved course and receives an x-ray certificate and is at least 18 years of age
Know the procedure regarding immersion disinfection
If any instruments are added to the solution before the disinfection time is up you must start timing all over
What causes films to turn brown and discolor after a few days?
Improper washing
Where is the thermometer placed?
In the water tank
What causes overlapping?
Incorrect horizontal angulation
What are the four body tissues most sensitive to radiation?
Intestinal tissue, embryo, cornea of the eye, and bone marrow
Besides gamma rays, what additional radiation wave from the EMR spectrum is considered harmful to tissue due to it's wavelength?
Ultraviolet
The value of radiographs for patient education includes?
•results of missing teeth •implant/bridges from restored mouths •results of reconstructive surgery •orthodontic conditions
The importance of an operator standing behind a lead shield when exposing x-rays is to prevent being exposed to?
•secondary radiation •direct radiation •scatter radiation •leakage radiation
Why is an ultrasonic cleaner preferred to hand scrubbing?
•uses waves to reach all areas of the instruments •uses a cavitation process •is safer for the auxiliary