A path less travelled — Short review on ossifying fibroma and osseous dysplasia

Abstract

Fibro-osseous lesions (FOL) are characterized by replacement of normal bone by fibrous tissue containing a newly formed mineralized product. The mineralized product may be ossification (sometimes cementum formation) or calcification of fibrous tissue by metaplasia. These lesions have similar radiographic and histopathologic features hence the term fibre- osseous lesion is not a diagnosis, rather a description of the presence of fibrous and calcified tissue. They may be developmental (fibrous dysplasia), reactive (cemento-osseous dysplasia) or neoplastic (ossifying/cementifying fibroma). This article presents the commonly used classification for fibro-osseous lesions and an insight into a few changes that have been introduced in the recent past with emphasis on Ossifying Fibroma and Osseous Dysplasia.Ossifying fibromas are considered as benign fibro-osseous neoplasms which are principally encountered within the jawbones. Cemento-osseous dysplasias are non-neoplastic fibro- osseous lesion. Since 1971, the World Health Organization classified cemental lesions into 4 distinct entities, as follows: Periapical Cemental Dysplasia, Benign Cementoblastoma (true cementoma), Cementifying Fibroma and Gigantiform Cementoma (GC). The term, gigantiform cementoma, may imply a solitary process but it is misleading because the condition typically presents as slow-growing, multifocal/multiquadrant and expansile lesions involving both jaws. WHO classified it in Osseous dysplasia and El-Mofty et al. under Ossifying fibroma.