Etiology:

• AD – microdeletion defect of transcription factor (CBFA-1) in chromosome 6
• Failure in intramembranous & endochondral ossification

Clinical:

Clavicle:

• Aplasia/ hypoplasia of 1 or both clavicles

Skull:

• Enlarged transverse diameter of cranium
• Short sagittal diameter of cranial base
• Delayed closure of fontanelles & sutures
• Wormian bones in suture lines

Teeth:

• Multiple supernumeraries
• Retrusion of maxilla
• Delayed eruption of permanent teeth

Diagnosis:

Radiograph:

Clavicle:

• Aplastic/ hypoplastic

Skull:

• Patent fontanelles & wormian bones
• Broad cranial sutures
• Underdeveloped nasal sinuses

Teeth:

• Multiple, unerupted supernumeraries

Histology:

• Teeth lack 2ry cementum (cellular cementum at apical two thirds)

Management:

• Protect with headgear in early life (open fontanelles)
• Surgical exposure of unerupted teeth + orthodontic therapy
• Orthognathic surgery
• Prosthesis