• Genetic and fibro-osseous disease
• Developmental jaw condition
• 100% penetrance in male, 50-75% in female (M:F = 2:1)
• Mean age 7 (1 – 12 years age)

Etiology:

• AD – mutation of SH3BP2 on chromosome 4
• Hyperactive macrophages and osteoclast – lead to bone loss and inflammation

Clinical:

• Teeth displaced and loose
• Painless bilateral expansion of mandible and maxilla (starts at 2-4 years)
• Therefore ‘cherubic’ exposure of sclera

Diagnosis:

X-ray:

• Multilocular expansile radiolucency – soap bubble appearance (ie. multilocular cysts)
• Opacification of sinuses

Histology:

• Vascular fibrous tissue with multinucleated giant cells
• Bone formation progresses as lesion matures

Serology:

• Normal calcium and phosphorus levels (to differentiate from Brown’s tumor)
• Increased alkaline phosphatase (due to increased bone turnover)

Management:

• Involution after puberty
• Surgery if persistent bone deformity

Differential diagnosis:

• Giant cell granuloma (differentiate with x-ray)
• Brown’s tumor (differentiate with calcium phosphate levels)
• Osteoclastoma (aggressive)

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