Exam II Material Flashcards
(72 cards)
What is the term for how well a boundary between two areas of differing radiodensity is revealed.
Sharpness
What is the term for how well a radiograph is able to reveal small objects that are close together
Spatial Resolution
What are the three ways that we can optimize image sharpness?
1.Small focal spot 2.Increase the distance between the focal spot and the object (use a long cylinder) 3.Minimize distance between object and image receptor
What happens if you decrease the distance from the focal spot to the object?
Image Size Distortion!
What are the two types of distortion mentioned?
Foreshortening and Elongation
_______ technique, the preferred method for making radiographs.
ParaLLeling Technique
In the Paralleling Technique, Placing image ______ parallel w/ ______ of tooth….Minimizes image ________.
receptor…long axis…distortion
To overcome some image magnification and loss of sharpness, use a relative _____ aiming cylinder “cone” to _____ the focal spot.
long…increase
What are the 2 ways we can Localize an Object?
1.SLOB rule 2.90 degree rule (2 views at 90degrees from each other)
What does it mean if we are trying to localize an object with the SLOB rule and the object does not move?
the object is neither buccal nor lingual… its in the middle!
What is this an example of? Expanded cortex is more opaque than the region inside the border as a result of the ________.
eggshell effect
In the picture ID slides, what is the structure that can cover the apex of the mandibular incisors?
the mental ridges
In the picture ID slides, what is the hole in the middle of the genial tubercles?
the Lingual foramen
In the picture ID slides, what are the dense pieces of cortical bone that are rare in the mouth?
tori
What is the total number of images in a FMX (CMS)?
18 (14PA’s & 4 BW’s)
Key point in rationale for imaging: use the correct imaging modality to match the ______ task!!!!
diagnostic
What is the main reason we don’t use CBCT in every day dentistry?
It can’t diagnose dental caries
For PA’s: see the entire tooth, including the root, plus at least ___ mm of bone past the root; if pathology is present, need to see the entire lesion and normal bone on one radiograph….For BW’s: each posterior ______ surface should be seen at least once (with no significant overlap)
2….proximal
Radiographs should have the least possible amount of _______—importance of correct receptor position & beam angulation
distortion
Radiographs should have optimal density and ______—use proper exposure settings
contrast
Central ray of beam directed at _______ to teeth and receptor.
right angles
the receptor is placed ______ to the teeth, _____ in the patient’s mouth
parallel…deep
What is a good technique if you are unable to apply the paralleling technique?
Bisecting Angle Technique (putting receptor along the angle of the central incisor)
When taking XRays: ALWAYS Use the ______!!! Acknowledge patient’s complaints regarding size of receptor, etc.; but don’t show too much _______; instead emphasize need for cooperation, perseverance, etc.; at the end of the exposures, express appreciation for the cooperation and ‘hard work’
lead apron….empathy
