Correction of a severe Class II malocclusion in a patient with Noonan syndrome.

Noonan syndrome is a developmental disorder characterized by a dysmorphic facial structure, short stature, and mild mental retardation, with associated cardiac defects and skeletal malformations. It may be sporadic or inherited as an autosomal dominant or recessive trait. The incidence of occurrence is 1 in 1000 to 2500 live births. The responsible gene is located on the long arm of chromosome 12. Diagnosis of the syndrome is made by both clinical inspection and karyotype. This is the case report of a 10-year-old Mexican boy who was referred for correction of orofacial and occlusal defects.