Radiology · patient case question
A radiopacity overlies the root of tooth 5. When the tube head is shifted distally, the object appears to move toward tooth 6, which is mesial. Where is the object?
Patient case: Reading the panoramic film
demo: Series of radiographic interpretation items
chief: Assorted radiographic findings and technique errors from a single clinic session.
history: Several patients imaged the same morning; the films are reviewed together at the end of the day.
meds: Not applicable.
findings: One panoramic film shows the right ramus and posterior teeth appreciably wider than the left. Another shows two ring-shaped radiopacities superimposed over one maxillary sinus and three over the other, in a patient wearing earrings. A third shows a curved radiopacity in the lower field. An occlusal film shows a soft tissue shadow over the incisal edges of the anterior teeth.
Show answer and explanation
Correct answer: A. Buccal
- A. Correct. The tube moved distally and the object moved mesially, which is the opposite direction. By SLOB, opposite means buccal. Working through it deliberately, rather than reciting the mnemonic, is what makes these items reliable.
- B. An object within the canal would not shift relative to the root at all; it would stay superimposed on it in both projections.
- C. A palatal object would have moved distally, following the tube in the same direction.
- D. The tube shift technique resolves buccal from lingual, not apical position, and an object apical to the root would not shift laterally in this way.