On a maxillary anterior periapical radiograph, a thin RADIOLUCENT vertical line runs between the roots of teeth #8 and #9. What is it?

Correct answer: B. The median palatal (intermaxillary) suture

• A. The NASAL SEPTUM is a broad RADIOPAQUE vertical structure superior to the incisive region, dividing the two radiolucent nasal fossae — opaque rather than lucent.
• B. CORRECT. The MEDIAN PALATAL SUTURE — also called the intermaxillary suture — is the fibrous joint between the two maxillary bones. On a maxillary central incisor periapical it appears as a thin, straight RADIOLUCENT line running vertically in the MIDLINE between the roots of #8 and #9, often bounded by two thin radiopaque cortical borders. It is a NORMAL anatomical landmark, not pathology, and requires no intervention.
• C. The INCISIVE FORAMEN appears as a rounded or heart-shaped radiolucency positioned between and APICAL to the central incisor roots — an oval or ovoid shape, not a thin vertical line.
• D. A vertical ROOT FRACTURE would be confined WITHIN a root, not running between two teeth in the midline, and would be accompanied by symptoms, a deep isolated pocket or a characteristic J-shaped or halo radiolucency.

Note: Maxillary anterior landmarks worth recognising as normal: median palatal suture (thin midline radiolucent line), incisive foramen (rounded midline radiolucency), anterior nasal spine (V-shaped radiopacity), nasal septum (broad midline radiopacity), floor of the nasal fossa (radiopaque horizontal line), and the nasal fossae themselves (paired radiolucencies).