Immunohistochemical expression of osteocalcin, transforming growth factor beta-1 and bone morphogenetic protein-7 in fibrous dysplasia and ossifying fibroma of the jaw bones (a comparative study)

Background: Fibrous Dysplasia (FD) & Ossifying Fibroma (OF) of the jaw are maxillofacial fibro-osseous lesions sharing an overlapping clinicopathological characteristics. This can be diagnostically challenging for pathologists. Materials and Methods: A total of 30 retrospective formalin- fixed, paraffine - embedded tissue blocks were included in this study, 15 were diagnosed as FD and the other 15 were OF of the jaw bones. An IHC staining was performed using OC, TGF-β1 and BMP-7 monoclonal antibodies was performed. Results: OC positive IHC expression was found in fibroblast-like cells in 4 cases(26.66%) of FD and in- 7 cases (46.67%) of OF, TGF-β1 was positively expressed in 8cases (53.3%) of FD and 10 cases (66.67%) of OF. BMP-7 showed positive expression in 2 cases (13.3%) of FD and 4 cases (26.7%) of OF. Conclusion: TGF-β1expression in most of FD & OF cases suggests its role in the process of osteogenesis. OC may be a helpful marker to differentiate between these two entities. However, further studies are required to verify this fact.