Central compact osteoma of the mandible: case report featuring unusual radiographic and computed tomographic presentations and brief literature review

Abstract

Central osteomas of the jaws have been infrequently reported, mostly presenting as a well-defined opacity on conventional radiography projections and as a hyperdensity on computed tomography scans. To increase the knowledge of the phenotypic expression of gnathic central osteomas, an unusual case has been described, including the clinical, radiographic, cone beam computed tomography (CBCT) and histopathologic findings. The lesion was initially discovered 4 years prior as an asymptomatic ovoid radiolucency in the posterior mandible.

A 25-year-old female presented with a hyperdense expansile mass with a hypodense rim on a CBCT scan. The enucleated mass was diagnosed as a compact central osteoma. A literature search has identified 4 other cases with similar hypodense borders on CT scans. We propose that a subset of central osteomas should be considered in the differential diagnosis of osteopathologies of the jaws with hyperdense internal architecture and hypodense borders, as seen on CT images.

Introduction

Craniofacial osteoma is an uncommon benign osseous tumor with an insidious growth rate, with a male predilection, and the mean age at diagnosis is 50 years [1]. Histopathologically, osteomas are characterized by 3 subtypes, as compact or ivory (composed of normal dense bone and scattered bone marrow spaces), cancellous (predominated by trabeculated bone and abundant fibroadipose marrow) and a mixed pattern (showing both histological features) [2].

Most osteomas are painless and arise in peripheral, central, and extraskeletal sites. The craniofacial skeleton is the primary location for osteomas, most frequently arising in the paranasal sinus and frontal bone, with fewer cases found in the jaws, predominately the posterior body of the mandible and less often in the maxilla and condyle [3]. Symptomatic patients often present with sinusitis, facial tenderness and asymmetry, headache and paresthesia [4]. Nonsyndromic peripheral and central osteomas typically appear as 1–2 firm structures, while cutaneous counterparts may exceed 100 in total [5]. Osteomas have been associated with Gardner syndrome, Haberland syndrome, Opitz G/BBB syndrome and acromegaly [6], [7].

A limited number of central osteomas (within medullary bone) of the jaws has been reported, principally in the molar-premolar region, and appearing as a well-defined radiographic opacity and as a hyperdensity on computed tomography scans. The aim of this article is to describe the unusual clinical, radiographic and cone beam computed tomography (CBCT) findings of a central compact osteoma of the posterior mandible.