An 11-year old female with monostotic fibrous dysplasia of the left zygomatic-maxillary region. A-C) Clinical photographs demonstrating the appearance. The lesion was quiescent and asymptomatic. It had grown slowly over a period of years. D) Her dentist noted delayed eruption of her teeth (*) on that side as well as mild facial asymmetry and obtained the panorex that identified the lesion. E-I) CT images demonstrate the pathognomonic appearance of FD for her age, a homogenous, “ground-glass” lesion. J) The reconstructed CT image gives a sense of the three dimensional shape of the lesion that accounts for the clinical appearance.