The role of Osterix protein in the pathogenesis of peripheral ossifying fibroma

Abstract

Peripheral ossifying fibroma (POF) is a reactive lesion of oral tissues, associated with local factors such as trauma or presence of dental biofilm. POF treatment consists of curettage of the lesion combined with root scaling of adjacent teeth and/or removal of other sources of irritants. This study aimed to analyze the clinical and pathological features of POF and to investigate the immunoexpression of Osterix and STRO-1 proteins. Data such as age, gender, and size were obtained from 30 cases of POF. Microscopic features were assessed by conventional light microscopy using hematoxylin-eosin staining and immunohistochemical markers, and by polarized light microscopy using Picrosirius red staining. The age range was 11-70 years and 70% of the patients were female. Moreover, the size of POF varied from 0.2 to 5.0 cm; in 43.33% of the cases, the mineralized content consisted exclusively of bony trabeculae. The immunohistochemical analysis showed nuclear staining for Osterix in 63% and for STRO-1 in 20% of the cases. Mature collagen fibers were observed in mineralized tissue in 76.67% of the cases. The clinical and microscopic features observed were in agreement with those described in the literature. Osterix was overexpressed, while STRO-1 was poorly expressed. Osterix was expressed particularly in cells entrapped in and around mineralized tissue, indicating the presence of a stimulus that triggers the differentiation of these cells into osteoblasts or cementoblasts, i.e., cells that produce mineralized tissue. Based on our results, Osterix may play a role in the pathogenesis of POF.

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

“…Peripheral ossifying fibroma (POF) is a common inflammatory/reactive lesion exclusively observed in the periodontal tissues. POF mostly affects the anterior maxilla of young adults and females, and local irritant factors such as trauma, dental biofilm, calculus, and irregular restorations have been associated with this lesion ( 1 , 2 ). Although POF pathogenesis remains unclear, it is believed that it may be originated from the gingival soft tissues or the periosteum as well as from the superficial periodontal ligament ( 3 , 4 ).…”

“…Clinically, POF arises as a gingival mass with a slow and progressive growing potential, generally without radiographic alterations, but radiopaque areas may be identified. The clinical appearance of POF resembles other gingival reactive lesions; thus, histopathological analysis is essential to the definitive diagnosis ( 1 , 2 ). POF is microscopically characterized by a highly cellular fibrous connective tissue composed of spindle-shaped and ovoid mesenchymal cells with vesicular nucleus and exhibit variable amounts of focal or extensive deposition of mature and/or immature bone, cementum-like tissue, and dystrophic calcification ( 3 , 4 ).…”

“…POF is microscopically characterized by a highly cellular fibrous connective tissue composed of spindle-shaped and ovoid mesenchymal cells with vesicular nucleus and exhibit variable amounts of focal or extensive deposition of mature and/or immature bone, cementum-like tissue, and dystrophic calcification ( 3 , 4 ). Also, a variable amount of inflammatory infiltrate and presence of ulceration may be observed ( 1 ).…”

Synchronous Reconstruction of the Jaw Using a “One and a Half”-Barrel Fibular Bone Graft for Ossifying Fibroma Patients

“…Besides, OF of the maxilla, which involves the nasal cavity and orbit, leads to expiratory dyspnea, nasal tilt, impaired vision, and diplopia. [9][10][11][12] On the other hand, however, OF of the mandible may affect the temporomandibular joint, leading to the restrictive opening of the mouth and other temporomandibular disorders. [13][14][15] Noteworthy, patients suffering from the disease are also psychologically drained.…”