Review for X-Ray Mod G Test
What is a form of radiation protection for the patient?
A lead apron (not a lead shield)
How is collimator accomplished?
A lead washer
Know 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 radiaitin considered harmful?
Because it is cummulative
What x-rays show the interproximal and are cavity detecting radiographs?
Bite wing x-rays
What are considered radiation protection for the operator during patient exposure?
Distance of 6-8 feet from tube Lead shield Double walled gypsum board
What is the hegatively charged particle that is respionsible for producing dental radiogrpahs?
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 the tooth is the?
Metal indicator rod
The cathode is:
Negative terminal
What films are extra oral films?
Panorex Cephalometric Orthopantomograph
The value of radiographs for patient education includes?
Results of missing teeth Implants/bridges form 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 radiaiton Leakage radiation
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
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
What causes foreshortening?
Too high a vertical angle
What is the purpose of the lead foil of a film packet?
Tp prevent secondary radiaiton from fogging film
What is distortion?
changes in the shape or size of an object
Identify the x-ray beam on the enclosed picture
not avalible --LOOK AT YOUR OWN DIAGRAM----
Why is a dental mask worn?
protect the mucous membranes of the nose and mouth
How much radiation is reduced by using Ultra Speed film?
65 %
What is contrast?
Difference between black, white, and shades of grey
The speed of electrons through a circuit is referred to as ?
Kilovoltage
What is th eoccupational 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 radiographs survey on a child?
3 years of age
What is the minimum allowable distance of the dark room safety light from the work 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 reticulation?
Cracking of the film emilsion 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 "California Law" ?
Dental assisstant who passes a board approved course and recieves an x-ray certificate (At least 18 yrs 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 the film to turn brown and discolor agter 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 tissue most sensitive to radiation?
Intestinal tissue Embryo Cornea of the eye Bone marrow
Besides gamma rays, what additional radiation wave from the EMR spectrum is considered harmful to tissue due to its wavelength?
Ultra Violet
Know why an ultrasonic cleaner is preferred to hand scrubbing?
Uses sound waves to reach all areas of the instruments Uses a cavitation process Is safer for the auxillary
