Radiology · patient case question
A structure appears on BOTH the panoramic radiograph and the lateral cephalogram, superimposed in the lower facial region. What is it?
Patient case: Films for a Patient Not Seen in Ten Years
Patient: 48-year-old male
Chief Complaint: “I want a full check-up. I know it's been a while.”
Background: Last dental visit approximately ten years ago. No current symptoms. Reports his gums bleed when he brushes.
Medications: None
Vital Signs: BP 128/80 mmHg · HR 76 bpm · RR 16 · T 98.4°F
Findings: Generalized 5–7 mm pockets with bleeding on probing and visible recession. Several teeth are slightly mobile. On imaging: a horizontally impacted #17 whose crown abuts the distal root of #18, which shows a concave defect at the contact point; a well-defined mixed radiolucent-radiopaque lesion at the apices of the mandibular anteriors, which all test VITAL; and a radiopaque structure superimposed over the mandible on both the panoramic and lateral cephalometric films.
Show answer and explanation
Correct answer: A. The hyoid bone
- A. CORRECT. The HYOID BONE. It is a U-shaped bone suspended in the anterior neck at about the C3 level and is the only bone in the body that articulates with no other bone. On a PANORAMIC film it appears as a radiopacity superimposed over the mandible bilaterally, or occasionally in the midline. On a LATERAL CEPH it is clearly visible in profile below and behind the mandible, and its position is used in airway analysis. Being asked to identify the same structure on both projections is a common item pattern.
- B. The cervical spine appears as a vertical ghost in the midline of a panoramic film and clearly in profile on a ceph, but not as a discrete structure over the lower face.
- C. The styloid process is visible on both films too, but it is a slender spine projecting downward and forward from the temporal bone, near the mandibular ramus — a different shape and location entirely.
- D. The soft palate is soft tissue. It is visible on a lateral ceph as a soft-tissue shadow but is not a distinct radiopacity superimposed over the mandible on a pano.
Note: Other panoramic landmarks worth being able to name on sight: the hard palate, the inferior border of the maxillary sinus, the zygomatic arch, the pterygomaxillary fissure, the mandibular canal, the mental foramen, the coronoid process, the ear lobe shadow and the ghost image of the opposite mandible.