Dental Radiography Flashcards
True or False: the dental radiograph unit is similar to standard full body radiograph unit
True
What are the three standard units of dental radiography?
milliampere (mA), peak voltage (kVp), time (s)
What are the 3 basic types of dental rad machines available?
Stationary (wall mount), portable (wheel based), handheld
True or False: Dental radiology units generally produce smaller volumes of radiation, but when repeat exposures are taken, the total exposure can become just as high as a standard x-ray unit
True
How far away should you be when obtaining dental radiographs?
Minimum of 6 feet away from the tube head & at a 90-135 degree angle from the tube head
What are you to do if you are unable to keep the required distance away from the tube head?
Wear PPE - lead gowns, thyroid shield
Dosimetry badge
True or False: Your hands can be in the primary beam of the xray
False
What are examples of positioning devices with dental rads?
Rolled gauze, tongue depressors, hair curlers, paper twoels
What are the 3 basic components of a dental xray machine?
xray tube head, adjustable arm, control panel
What is in the tube head of the dental rad machine?
Cathode and anode are located w/in the tube head
Its the location where the production of x-rays occur
What is a position indicating device (PID)?
Its contained in the tube head;
It helps collimate the xrays and provide less scatter radiation
The ______ the PID is to the patient & film, the _____ the image will be due to ______ in scatter radiation
closer; better; decrease
What is the tube head attached to?
An adjustable arm
What does the adjustable arm do?
Allows movement of the tube head and is used to hold the tube head in place while xrays are taken
What does the control panel contain?
unit settings (preset)
What is the most common setting that can be adjusted?
Time
What does a pictogram of the animal’s oral cavity allow?
Allows the tech to select the size of the animal and select the tooth being imaged
What is used if the control panel doesn’t contain a pictogram or kVp and mA are not preset?
A technique chart
What are the three types of image receptor devices in dental radiology?
film, digital sensors, phosphor plates
True or False: Intraoral dental films comes in different speeds just as with standard radiography film
True
What occurs with fast film?
It requires less radiation but results in an increase grain of the image
What film types are commonly used?
D, E, F –> requires less radiation to produce the image
D type film
most commonly used in vet med
Comes in different sizes (0,2,4 - most common)
What does the foil sheet do in packaged film?
Its used to decrease scatter radiation
What does the black paper do for the film?
It surrounds it for protection
What is an advantage of digital dental radiology?
50-90% reduction in radiation needed to produce an image; the image is also immediately available
What is the most common sensor size for digital dental imaging?
Size 2 (some produce a size 4 sensor)
What must be placed on the sensor to help prevent cross-contamination?
protective hygiene sleeve; add a layer of vet wrap around the sensor to help hold the sensor in place while taking rads
What happens if a facility doesn’t have size 2 and 4 sensors?
multiple views are to be taken of the entire tooth for larger teeth
What is the phosphor plate system?
a unique system that combines the versatility of film w/ benefits of digital imaging
what are the advantages of phosphor plates?
ease of use, versatility, availability of multiple sizes of plates (from 0-6), and no chemicals needed for processing
What is the primary drawback for phosphor plates?
high initial cost of the unit
removing of the plate for prcoessing can make retakes more difficult because identical replacement of the film in the oral cavity is difficult
How are intraoral films developed?
Using a chair-side developer but it can take hours to dry
What is a chairside developer?
A lightproof box that has 2 hand holes in the front & a translucent filter lid on top to allow the tech to see what they’re doing while processing the film
What are the 3 patient positions for dental rads?
sternal, dorsal, lateral
What is the goal of dental imaging? How does it occur?
get as much root as possible; place the crown of the tooth to the edge of the sensor
How many films are taken for a cat? For a dog?
Cat: 8 films
Dog: 12 films
What are the two standard intraoral radiograph techniques?
parallel technique, bisecting angle technique
What is the parallel technique?
- easiest to master
- same theory used in the oral cavity that is used for lateral imaging of the body
- used to obtain images of the mandibular fourth premolars and molars in dogs & cats
How do you set up a radiograph using the parallel technique?
- sensor is placed in the mouth parallel to the teeth being imaged
- PID is placed as close to the patient as possible
- patient should be in dorsal recumbency
- tube head should be placed at 0 degrees so that it’s directly perpendicular to the tooth
- important: when obtaining images of molars in the dogs that the sensor is placed AS FAR BACK in the mouth as possible so that the last molar tooth is images
What is the bisecting angle technique?
- obtains images of teeth within the hard palate of the maxilla and mandibular symphysis
- uses the plane of the root of the tooth of interest, compared to the plane of the sensor when placed in the oral cavity
- a line halfway between these two lines makes up the bisecting angle
- PID is placed parallel and as close to the patient as possible and on the imaginary bisecting angle line
What can you do to take images of patients in sternal recumbency?
place a towel or fluid bag under their chin - helps to maintain this parallel positioning
