2d. OPG Views and Positioning Flashcards
how does the OPG machine work
in terms of the xray tube and IR
Xray tube orbits around back of head and IR moves infront of face
the tube and IR move in opposite directions
what beam technology does the OPG machine use
what is this used for
split beam technology
slit collimation reduces radiation exposure to eyes and thyroid
what 3 structures does the OPG provide images of
provide panoramic view of teeth, mandible, TMJs
what are laser light used for in OPG views
what plane does the laser pass through
used to center in midline of patient
laser light passes through frankfort plane
what is the frankfort plane
superior border of external auditory meatus to infraorbital margin
what is the frankfort planes position in relation to the floor
parallel
what must be done to head clamps in OPG
tighten clamps
what is the exposure time like in OPG
long exposure time ~14sec
finger kept on exposure switch
what is the image criteria for the OPG views in terms of area of interest
whole of mandible demonstrated
front and back teeth in focus
what is the image criteria for the OPG views in terms of rotation and tilt
no rotation or tilt
check TMJs are in the same plane and rami are equidistant
what position does the jaw need to be in for OPG
jaw in gentle smile position
what is the panelipse too smiley potential image error potentially caused by
how can this be corrected
chin too flexed
correct by lifting the chin a little
what is the panelipse too sad potential image error potentially caused by
how can this be corrected
chin too extended
correct by dropping the chin a bit
what is the teeth squeezed together potential image error potentially caused by
patient positioned too far forwards
what is the teeth pulled apart potential image error potentially caused by
patient positioned too far back
