Radiology · patient case question
A dense radiopaque band is seen running downward and forward from the anterior border of the ramus across the mandibular molar region. Which structure is this?
Patient case: Radiographic anatomy and removable design
Scenario: Three opening items: one radiographic landmark, one RPD component, one shade-selection decision.
Show answer and explanation
Correct answer: D. External oblique ridge
- A. Nutrient canals are fine radiolucent lines, most often seen interdentally in the anterior mandible, and are far thinner than this band.
- B. The mandibular canal is a radiolucent band with corticated superior and inferior borders running from the mandibular foramen to the mental foramen.
- C. The mylohyoid groove is lingual and appears as a thin radiolucent line running downward and forward from the lingula — radiolucent, not radiopaque.
- D. Correct. The external oblique ridge is a buccal cortical thickening that continues from the anterior border of the ramus and sweeps anteroinferiorly over the molars, casting a broad radiopaque band.