Atlas · Plate IX · Dental Radiography · 08
Panoramic imaging
A panoramic unit sharpens only structures inside its focal trough. Correct positioning puts the Frankfort plane parallel to the floor, the midsagittal plane vertical, the incisors edge to edge in the bite block and the tongue on the palate. Positioning errors leave classic signs: a smile or frown occlusal plane, narrow or wide anteriors, or a spine shadow.
High-yield facts · 9
- The panoramic image uses a focal trough (image layer); structures outside it are blurred, magnified or narrowed.T7
- Positioning: Frankfort plane parallel to the floor, midsagittal plane perpendicular, teeth edge to edge in the bite block, tongue on the palate.T7
- Too far forward: narrow, blurred anterior teeth. Too far back: wide, blurred anterior teeth.T7
- Head turned or tilted: one side's teeth wider than the other and uneven rami.T7
- Chin too low: exaggerated smile and overlapping hyoid. Chin too high: flat or frown-shaped occlusal plane, broad palate shadow over maxillary roots.T7
- Slumped spine: triangular radiopacity (cervical spine) in the middle of the image.T7
- Ghost images appear on the opposite side, higher and blurred (e.g., earrings, the hyoid, the opposite ramus).T7
- Panoramic images are poor for detecting proximal caries and fine bone detail; they show third molars, large lesions, fractures and the TMJ area.T7S19
- Lead apron for panoramic imaging is no longer recommended routinely; if a state requires one, it must not block the beam (no thyroid collar).S21
Facts are written in our own words; each tag links to its source. Values marked "sources vary" differ between references, so check the one your program uses.