Quiz 4 Chapter 8 Flashcards
The portion of a dental image that appears dark or black is termed:
Radiolucent
The portion of a dental image that appears light or white is termed
Radiopaque
Which appears most radiolucent on a dental image?
air space
The overall blackness or darkness of a dental image is termed
Density
Increasing the mA will cause
an increase in density, the image appears darker
Increasing the operating kilovoltage will cause:
an increase in density the image appears darker
Increasing the exposure time will cause
an increase in density, the image appears darker
A dental patient has thick soft tissues and dense bones. To compensate for this increase in subject thickness and to provide an image of diagnositc density, the dental radiographer may:
increase milliamperage
increase the exposure time
increase the kilovoltage
The difference in the degrees of densities between adjacent areas on a dental image is termed:
contrast
A dental image that demonstrates many shades of gray is said to have
low contrast
A dental image that demonstrates very dark areas and very light areas
high contrast
Fig 8-16 what exhibits high contrast
A
Fig 8-16 what exhibits low contrast
B
Fig 8-16 what exhibits long scale contrast
A
Fig 8-16 what exhibits short scale contrast
B
Fig 8-16 Which exhibits no contrast
C
The one exposure factor that has a direct influence on the contrast of a dental image is
kilovoltage
The type of contrast preferred in dental imaging is:
low contrast
The stepwedge is used for all of the following except
to increase the penetrating quality of the x ray beam
The capability of the receptor to reproduce distinct outlines of an object is termed:
distortion
The unsharp or blurred edges seen on an image are termed
penumbra
A variation in the true size and shape of the object being imaged is termed:
distortion
Decrease focal spot size
increase sharpness
Increase movement ___
decrease sharpness
Increase Crystal size
decrease sharpness
Decrease crystal size ___
increase sharpness
Decrease object receptor distance
increase sharpness
Increase target receptor distance =
decreases magnification
Increase object-receptor distance =
increase magnification
Decrease object receptor distance
decrease magnification
Object and receptor are parallel
decrease distortion
Beam perpendicular to object and receptor
decrease distortion
Beam not perpendicular to object and receptor =
increase distortion
