Fibrous dysplasia of the mandible typically begins during toddler years
and culminates during puberty. These lesions may cause jaw disfigurement
and may not be amendable to surgery. Imatinib successfully has treated
cherubism associated with SH3BP2 mutations, but similar lesions
can present in other conditions such as Noonan syndrome. We report
diagnosis of Noonan syndrome caused by a PTPN11 activating
mutation and successful treatment of the fibrous dysplasia of the
mandible with imatinib.