Panoramic Errors & Landmarks PDF

# Panoramic Errors & Landmarks ## Subject: ### Mode: - Head seated on the chin rest - Bite: Light of the biting block at the notch. Laser light of the midsagital plane should be on the floor, & the Frankfurt plane // floor. - Canine lines determine arch curvature. U, V, U It has no indication...

# Panoramic Errors & Landmarks ## Subject: ### Mode: - Head seated on the chin rest - Bite: Light of the biting block at the notch. Laser light of the midsagital plane should be on the floor, & the Frankfurt plane // floor. - Canine lines determine arch curvature. U, V, U It has no indication for image errors, but helps to determine how close we are with the focal trough (how the machine proposes the arch shape). ## Technique Errors - Chin tilted up or down - Frankfurt plane isn't // floor - Head twisting (rotating off-center) - Cone side is magnified and blurred (midsagittal plane not I floor) (Ls in the horizontal dimensions) - Arch's teeth not aligned in the focal trough ### Head tilting - One side appears at a higher position as the condyle at one side is closer to the periphery of the film than the other condyle. Also, the angle of the mandible appears at a higher site than the opposite side. Also the higher side is larger. ### Head is positioned too far anteriorly - Pt bite anteriorly to the notch of the bite block - Anterior teeth seem to be smaller in width. - S looks long - S looks blurry. (out of focal trough) ### Head is positioned too far posteriorly. - Pt bite posteriorly to the notch of the bite block - Anterior teeth appears widened in size (away from cassette) - S appear blurry (out of the focal trough) ### Chin tilted downward (head tilted forward) - not aligned - Frankfurt plane is not // to the floor. - Mandible appears in V-shaped & exaggerated. - Smile line & lower anterior blurred (out of focal trough) - S appear shorter, but widened (away from cassette) also magnified. - In that case, the condyles may be cutoff from the film, or chin is cut from the film. Both errors can occur or seen at the same time. ### Chin is tilted upward (head tilted backward) - Frankfurt plane is not // Floor - Upper anteriors appear blurred, shorter & magnified (wide also condyles would be cut off the film laterally (lateral condyle cut off) ## Cause ### Improper chin support - Pt doesn't place chin on chin rest. - Nasal cavity, maxillary sinus & infra-orbital rim - S superior condyle cut off ### If Pt wears earrings, It should be mentioned - Foreign body (metal artifact) covers the anatomical structures. - S may cause ghost image (Point 9 & 12 related) ### Improper tongue position - Pt doesn't elevate his tongue to the hard palate during imaging. - Tongue (radiolucency) - Teeth are super imposed on the apices of the upper teeth. ### Movement - Pt is not still during imaging. - The whole image appears blurry. Also step cut at the inferior border of the mandible. Also structures at the image are superimposed on each other. ### Ghost image. - Pt doesn't remove metal objects (effect) (error (metal artifact) before imaging) - Radio-opaque artifact appears as the real object, but blurred, magnified & at a higher level on the opposite site superimposed on the anatomical structures. # Normal structure that has ghost image but doesn't bother us (ramus & inferior border of the mandible). ### Lead apron artifact - Improper placement of thyroid collar or lead apron. - Cone shaped artifact at the midline. Normally, it doesn't reach the upper teeth. ### Improper posture - Pt back is not straight, (slumped) - Error name (cervical spine artifact) - White radio-opacity at the midline. It would appear superimposed over them as it was inside the focal trough (so, it was not at the sides of the film as their normal view)