[Hemifacial microsomia: development, diagnosis and surgical correction]

Hemifacial microsomia is the second most common congenital facial anomaly. It occurs as a spontaneous event during embryogenesis and involves structures derived from the first and second branchial arch. In the past treatment of the skeletal defect was delayed until the child ceased growing and end-stage of the deformity was reached. More recent approach to analysis and treatment of this anomaly, emphasizing early treatment, to give the patient the maximum benefit of a combined surgical and orthodontic therapy, is described.