Peripheral ossifying fibroma: A 20-year retrospective studywith focus on clinical and morphological features

ABSTRACT

Background: Peripheral Ossifying Fibroma (POF) is a reactive hyperplastic lesion that exclusively occurs in thegingiva and is characterized by the deposition of dystrophic calcification, cementum-like tissue, and immatureand mature bone within the connective tissue. The objective of the present study was to perform a retrospectiveanalysis of clinicopathologic features of POF.Material and Methods: Clinical and histopathological data were obtained from biopsy records and histopathological reports from a Brazilian reference service in Oral Pathology (1999 - 2020). Morphological analysis wasperformed to evaluate features related to the mesenchymal component, inflammatory infiltrate, ulceration, andmineralized tissue.Results: A total of 270 POFs were diagnosed during the study period. A higher frequency was observed in females(71.9%) between the third (22.9%) and fourth (23.3%) decades of life. The anterior upper gingiva (29.1%) wasthe most affected region. Mature (86.7%) and immature (52.6%) bone tissue were the most frequent. There was asignificant association between immature bone deposition and lesions with size ≤ 1.7 cm (p = 0.041); immaturebone and cement-like tissue deposition with an evolution time ≤ 16 months (p < 0.001); deposition of immaturebone and mesenchymal hypercellularization (p < 0.001); deposition of dystrophic calcification and the presenceof ulceration (p < 0.001).Conclusions: The clinical characteristics corroborate the findings in the literature. The heterogeneous distributionand quantity of mineralized tissues found in the analyzed cases support the theory that the different mineralizedtissues constitute a spectrum of clinical maturation of POF. (AU)