Cherubism

Cherubism is a rare genetic disorder that causes progressive bilateral painless swelling of the face, typically appearing in early childhood. It primarily affects the mandible (lower jaw) and maxilla (upper jaw).

Etiology:

Cherubism is typically inherited in an autosomal dominant pattern, meaning only one copy of the mutated gene is necessary to express the condition. The gene most commonly associated with cherubism is SH3BP2, located on chromosome 4p16.3. Mutations in SH3BP2 affect osteoclast formation and activity, leading to increased bone resorption in the jaws. While most cases are inherited, spontaneous mutations can also occur.

Clinical Presentation:

The characteristic feature of cherubism is bilateral swelling of the lower face. This swelling is usually symmetrical and painless. The onset of swelling typically occurs between the ages of 2 and 5 years. As the condition progresses, the swelling can extend to the maxilla, giving the child a rounded, cherubic appearance, hence the name of the disorder.

Other common features include:

• Premature loss of primary teeth
• Delayed eruption of permanent teeth
• Malocclusion (misalignment of teeth)
• Displacement of teeth
• Expansion of the jaws, potentially affecting speech and swallowing.
• Upward tilting of the eyes (giving a 'looking towards heaven' appearance) due to maxillary involvement.
• Radiographic findings often reveal multilocular radiolucencies ("soap bubble" appearance) within the affected bones.

Diagnosis:

Diagnosis of cherubism is typically based on clinical findings, radiographic imaging (panoramic radiographs, CT scans), and family history. Genetic testing for mutations in the SH3BP2 gene can confirm the diagnosis.

Treatment:

There is no cure for cherubism. Treatment is aimed at managing the symptoms and improving the patient's quality of life. Management may involve:

• Observation: In mild cases, observation may be sufficient, as the condition often regresses after puberty.
• Surgical intervention: In more severe cases, surgical removal of the affected bone may be necessary to reduce the swelling and improve facial aesthetics. This can include curettage, bone grafting, or contouring procedures.
• Orthodontic treatment: To correct malocclusion and improve dental function.
• Speech therapy: If speech is affected.
• Genetic counseling: To inform families about the inheritance pattern and recurrence risk.

Prognosis:

The prognosis for cherubism is generally good. The condition typically stabilizes or regresses after puberty, although some bony deformities may persist. Surgical intervention can improve facial aesthetics and function. Regular dental care is essential to maintain oral health.