Fibrous dysplasia is a benign fibro-osseous disease that affects 1 or more bones. Deformities leading to aesthetic and functional disorders are observed in almost all cases. Plastic surgery is often recommended when the jaws are involved. Monostotic fibrous dysplasia of the mandible is an unusual manifestation of the disease that is usually benign, occurs in young individuals, and is managed by conservative curettage or debridement, such as surgical sculpting. The authors report a case of a 15-year-old patient with a large monostotic fibrous dysplasia located in the right mandible, which was treated by contouring bone. The lesion did not recur on follow-up for 4 years after the surgical procedure.