Radiology · patient case question
What is the finding in Patient B?
Patient case: Two normal structures mistaken for pathology
Patient: Two patients
Chief Complaint: Both attend for routine radiographic examination.
Background: A, 48-year-old female: mandibular anterior teeth all respond normally to cold and are non-tender. B, 9-year-old male: no history of trauma; referred for assessment before orthodontic treatment.
Findings: A: a periapical of the mandibular anteriors shows a well-defined radiopaque RING in the midline near the inferior border, with a small central radiolucency. B: a maxillary occlusal film shows a thin radiolucent LINE running anteroposteriorly in the midline of the palate, with faintly sclerotic margins.
Show answer and explanation
Correct answer: A. The median palatal (intermaxillary) suture — normal anatomy
- A. CORRECT. The MEDIAN PALATAL SUTURE, also called the intermaxillary suture, runs anteroposteriorly in the midline between the two maxillae. On a maxillary occlusal film it appears as a thin radiolucent line beginning between the central incisors and extending posteriorly, often with slightly sclerotic corticated margins. It is normal anatomy at any age. Its clinical relevance is orthodontic: this is the suture opened by RAPID MAXILLARY EXPANSION, and the expansion achievable depends on the patient's age and the degree of sutural interdigitation — which is why skeletal expansion is straightforward in a nine-year-old and requires surgical assistance in an adult.
- B. A palatal fracture line would be irregular and NON-corticated, would follow a history of significant trauma, and would usually be accompanied by displacement, occlusal disruption or mobility of a segment. The stem specifies no trauma and describes sclerotic margins.
- C. A midline alveolar cleft produces a wide, irregular separation with disturbed alveolar contour and abnormal dental anatomy at the cleft margins, not a thin corticated line.
- D. A nasopalatine duct cyst is a ROUND, oval or heart-shaped radiolucency at or just posterior to the incisive foramen — not a thin line running the length of the palate. It is diagnosed when it exceeds roughly 6 mm or produces symptoms or expansion.
Note: The maxillary occlusal film contains a cluster of normal midline structures worth naming confidently: the median palatal suture, the incisive foramen and canal, the nasal septum with the two nasal fossae flanking it, and the anterior nasal spine. Confusing any of them for pathology leads to unnecessary investigation of a healthy child.