The aim of this report is to describe the combination of Crouzon syndrome and acanthosis nigricans with fibrous dysplasia of the maxilla. The diagnosis of fibrous dysplasia was confirmed clinically and pathologically during Le Fort III osteotomy and midface advancement with distraction osteogenesis. Crouzon syndrome with acanthosis nigricans is a known syndrome with an incidence of 1:1,000,000. This is the first report in the literature of Crouzon syndrome and acanthosis nigricans combined with fibrous dysplasia. As all 3 pathologies are related to fibroblasts, they may be different manifestations of malfunction of a single molecular pathway. The detection of fibrous dysplasia in a patient with Crouzon syndrome and acanthosis nigricans is important because it may complicate midface osteotomies and fixation of the hardware on the bones during craniofacial surgery.
