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Eversole R, Su L, ElMofty S: Benign fibro-osseous lesions of the craniofacial complex. A review.
Head Neck Pathol. 2008 Sep;2(3):177-202. Epub 2008 May 13.

Benign fibro-osseous lesions of the craniofacial complex are represented by a variety of disease processes that are characterized by pathologic ossifications and calcifications in association with a hypercellular fibroblastic marrow element. The current classification includes neoplasms, developmental dysplastic lesions and inflammatory/reactive processes. The definitive diagnosis can rarely be rendered on the basis of histopathologic features alone; rather, procurement of a final diagnosis is usually dependent upon assessment of microscopic, clinical and imaging features together. Fibrous dysplasia and osteitis deformans constitute two dysplastic lesions in which mutations have been uncovered. Other dysplastic bone diseases of the craniofacial complex include florid osseous dysplasia, focal cemento-osseous dysplasia and periapical cemental dysplasia, all showing a predilection for African descent individuals; although no specific genetic alterations in DNA coding have yet to be uncovered and most studies have been derived from predominant high African descent populations. Ossifying fibromas are neoplastic lesions with four subtypes varying with regard to behavior and propensity for recurrence after surgical excision. The clinicopathologic and molecular features of this unique yet heterogeneous group of diseases are reviewed.

[PubMed]
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Slootweg PJ: Maxillofacial fibro-osseous lesions: classification and differential diagnosis.
Semin Diagn Pathol. 1996 May;13(2):104-12. [PubMed]

A large diversity of lesions may involve the maxillofacial bones. Some occur exclusively at this site. Other lesions at this location have features that are different from similar lesions occurring elsewhere in the skeleton. This site-dependent morphology applies especially to fibro-osseous lesions, which will be discussed in this report. Fibrous dysplasia shows evenly distributed islands of woven bone that fuse with surrounding bone. The presence of lamellar bone and osteoblastic rimming does not contradict that diagnosis as they would for lesions occurring outside the maxillofacial bones. Ossifying fibromas are demarcated or encapsulated. They show a broad variation in mineralized material that may be woven bone as well as lamellar bone or may be present as rounded cell-poor particles regarded as a form of cementum. Specific subtypes are juvenile ossifying fibroma and psammomatoid ossifying fibroma, both of which contain cellular stroma exhibiting mitotic activity. Lesions known as periapical cemental dysplasia can be found in the tooth-bearing jaw area and are similar to ossifying fibroma but without demarcation. These lesions may be focal, involving one or a few adjacent teeth; when they are more widely distributed, they are named florid cemento-osseous dysplasia. Periapical cemental dysplasia should be distinguished from cementoblastoma, a lesion similar to osteoblastoma but connected with tooth apices. Ossifying fibroma may resemble well-differentiated osteosarcoma as ossifying fibroma may be more cellular and may have a higher number of mitoses than osteosarcoma. [PubMed]