Pediatric Dentistry · patient case with 3 questions
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.
Question 1
Which additional finding would you most expect on further examination of this patient?
Show answer and explanation
Correct answer: C. Dry eyes and reduced salivary flow
- A. Incorrect. Blue sclerae reflect thin scleral collagen and point to osteogenesis imperfecta or Ehlers-Danlos syndrome, not to a defect of ectodermal derivatives.
- B. Incorrect. Palmoplantar hyperkeratosis is a feature of Papillon-Lefèvre syndrome and would be accompanied by aggressive periodontal destruction, not congenital tooth absence.
- C. Correct. Ectodermal dysplasia affects all structures of ectodermal origin, and that includes the lacrimal, salivary, nasal, and bronchial glands. Reduced tear production causes dry, irritated eyes, and reduced saliva causes xerostomia with a markedly elevated caries risk.
- D. Incorrect. Clavicular abnormality points to cleidocranial dysplasia, where clavicles are hypoplastic or absent — which allows the shoulders to approximate — rather than bulbous.
Question 2
To whom should this patient be referred for coordination of long-term care?
Show answer and explanation
Correct answer: B. A pediatric dentist to coordinate multidisciplinary management
- A. Incorrect. Conical teeth are a morphologic variation, not a pulpal problem. There is no indication for endodontic treatment.
- B. Correct. Management spans prosthodontics, orthodontics, oral surgery, and general medicine over many years of growth. The pediatric dentist is the appropriate coordinator, typically beginning with removable overdentures in early childhood and revising them as the child grows.
- C. Incorrect. Implants are contraindicated in a growing patient because the fixture behaves as an ankylosed unit and becomes progressively infraoccluded as the alveolus develops. The anterior mandible is the only site sometimes considered early, and that is a specialist decision made much later.
- D. Incorrect. Orthodontics has a role, but with so few teeth present there is nothing to align at this stage, and it is not the entry point to care.
Question 3
Setting this patient aside, which teeth are most frequently congenitally absent in the general population?
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.