Pediatric Dentistry · patient case question
Setting this patient aside, which teeth are most frequently congenitally absent in the general population?
Patient case: Sparse Hair, Dry Skin, Missing Teeth
Patient: 9-year-old male
Chief Complaint: Mother: “He has almost no teeth, and he can’t handle hot weather at all.”
Background: Recurrent unexplained fevers each summer, previously attributed to viral illness. Two maternal uncles reportedly “had the same teeth problem.” Normal cognitive development.
Medications: None
Vital Signs: BP 98/62 mmHg · HR 88 bpm · RR 18 · T 98.8°F
Findings: Sparse, fine, light-colored scalp hair; sparse eyebrows. Frontal bossing, depressed nasal bridge, protuberant lips, and fine wrinkling of periorbital skin. Skin dry and smooth; mother reports he almost never sweats. Intraorally, several conical anterior teeth and multiple missing teeth with knife-edge alveolar ridges.
Show answer and explanation
Correct answer: D. Third molars and maxillary lateral incisors
- A. Incorrect. First molars and canines are the least commonly absent permanent teeth in either arch.
- B. Incorrect. Mandibular central incisors are occasionally absent, but maxillary canines are among the least likely teeth to be congenitally missing — they are far more commonly impacted than absent.
- C. Incorrect. Maxillary lateral incisors belong on the list, but maxillary first premolars are rarely congenitally absent.
- D. Correct. Third molars are by a wide margin the most commonly absent teeth. Once third molars are set aside, mandibular second premolars and maxillary lateral incisors compete for the top position, with maxillary laterals the most frequently cited in the anterior region.
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