Pathology · patient case question
All of the following are features of cleidocranial dysplasia EXCEPT one. Which is the EXCEPTION?
Patient case: Delayed eruption and a narrow chest
Patient: Female, 12 years old
Chief Complaint: “My adult teeth never came in.”
Background: Father had a similar dental history. No systemic illness.
Findings: Frontal and parietal bossing, hypertelorism. She can approximate her shoulders in front of her chest. Panoramic radiograph: multiple retained primary teeth, numerous unerupted permanent teeth and several supernumerary teeth.
Show answer and explanation
Correct answer: C. Mandibular retrognathism
- A. Retained deciduous teeth are the rule, since the permanent successors do not erupt on schedule and the primary teeth have no reason to exfoliate.
- B. Supernumerary teeth are a cardinal feature, concentrated in the anterior and premolar regions, and they are a major reason the permanent teeth fail to erupt.
- C. CORRECT as the exception. The mandible in cleidocranial dysplasia is essentially normal in size, while the MAXILLA is hypoplastic — so the face reads as relative mandibular PROGNATHISM, not retrognathism. Midface deficiency with a pseudo-Class III profile is the recognised pattern.
- D. Delayed closure of the fontanelles and sutures is part of the defining triad; wormian bones are often present as well.