Imaging techniques Flashcards
Types of IO Xrays
PA, BW, Occlusal
Periapical
2-3 teeth crown to apex
BW
usually done in pairs
Horizontal bite block: U/L PM and 1st/2nd Molar
Vertical: More root less teeth
Occlusal
Larger area than PA and BW
Types of EO Xray
Panoramic Lateral Cephalometric Oblique lateral Occipito-mental Postero-anterior
Panoramic
DPT - dental panoramic tomography
OPG - orthopantomograph
Patient in centre of machine
All teeth and supporting structures imaged
Lateral cephalometric
Relationship of U/L arches and soft tissue outline.
Lateral view of facial bone and jaw.
Position using cephalostat.
Oblique Lateral
U/L posterior teeth on one side
Good if you can’t access mouth - kids, disabilities
Side of interest against image receptor
Postero-anterior PA
Chin down, occopit up
Face on mandible view
Occipito-mental OM
Chin up
Dense skull structures based below facial bones on image
CBCT
Cone beam computed tomography
Good for bone
Bad soft tissue
Cone shaped beam xrays
CT
Computed tomography
Good bone and ST
Xrays thin sections
Ultrasound
High frequency sound waves
No risk - used on thyroid, glands, during pregnancy
Bad bone
Good ST
MRI
Magnetic resonance imaging
Good for bone and ST
Strong magnetic filed lines up protons in H+ atoms
Short bursts of radio frequency knock protons out of alignment
As proton realigns a rotation induces and electrical signal in receiving coil
Can distinguish between different types of tissue
Radionuclide imaging
Pharmaceutical attached to radioisotope. Detected by gamma camera.
Good bone and ST
