Non-ossifying Fibroma of Mandible in a Four-Year-Old Girl: A Case Report

Abstract

Non-ossifying fibroma (NOF) is not prevelant in the mandible. It appears mostly in the long tubular bones in children and adolescents. We are presenting a case of a four-year-old girl reported to the maxillofacial department with painless swelling over the lower right side of the jaw. On the orthopantomogram (OPG), a well-defined multilocular radiolucency with a sclerotic margin was present. On computed tomography (CT), an expansile lytic lesion with cortical thinning without a breach in cortical continuity was noted. By correlating clinical and radiological features, a diagnosis of odontogenic and/or osteogenic lesion was made. The patient was considered for an excisional biopsy with curettage. On histopathology, NOF was confirmed. On postoperative follow-up, there was no sign of recurrence, and bone regeneration was significant.

Keywords: fibrous cortical defect; histiocytic xanthogranuloma; malignant fibrous histocytoma; metaphyseal fibrous defect; non-ossifying fibroma.

Figure 1. Frontal facial profile

Frontal facial profile showing facial asymmetry due to the presence of diffuse swelling over the right angle region of the jaw.

Figure 2. Orthopantomogram

Orthopantomogram revealed a  well-defined multilocular radiolucency located at the angle region of the right mandible.

Figure 3. CT face plain axial section

On CT face plain axial section bone window, a well-defined expansile lytic lesion was noted arising from the angle of the mandible on the right side, extending anteriorly till the deciduous molar tooth. Significant cortical thinning along with buccal expansion was noted at the perilesional area. No evidence of an obvious cortical breach was noted.

Figure 4. CT face plain coronal section

On CT Face plain coronal section bone window, a well-defined expansile lytic lesion was noted arising from the angle of the mandible on the right side extending superiorly till the upper border of the mandible, inferior border of mandible inferiorly. Significant cortical thinning was noted at the perilesional area. No evidence of an obvious cortical breach was noted.

Figure 5. Histopathology study

A stellate to spindle fibroblastic cells amidst myxoid background and reactive bone formation with osteoblastic rimming are seen. The spindle cells had sparse eosinophilic cytoplasm and oval nuclei. There was a focal cluster of osteoclast giant cells seen around the bone as well as singly scattered amidst the stroma.

Figure 6. A panoramic radiograph taken during the one-year follow-up

The red arrow shows persistent bone consolidation around the right mandibular angle.