Central ossifying fibroma of mandible arising in association with cemento-osseous dysplasia. An unusual case presentation

Abstract

<h3>Introduction</h3> Cemento-osseous dysplasia (COD) is known to develop complications including infection, necrosis, and traumatic bone cysts [1]. Neoplastic occurrence with COD has been reported, but is rare [2,3]. We report an unusual case of central ossifying fibroma (COF) of the mandibular symphysis in association with COD in a 46-yearold black female. <h3>Case Description</h3> The patient presented with a mandibular symphysis mass that was associated with difficulty of eating, speaking and paresthesia. The radiographic images showed a predominantly radiopaque mass in the symphysis region, measuring 7 × 6 × 5cm. There were discrete, minimally expansile mixed radiolucentopaque lesions in the posterior mandible and maxilla. The patient underwent mandibular resection due to the symptoms of eating and speaking difficulties as well as paresthesia. Before resection, three incisional biopsies including bilateral posterior regions of mandible and the central mass. Histopathologic examination of posterior specimens revealed similar findings of fragments consisting of cellular fibroblastic tissue intermixed with short bone spicules and cementum-like and hemorrhagic deposits associated with traumatic bone cysts. However, the central specimen showed solid tumor consisting of fibroblastic proliferation supporting spindled fibroblast-like cells. It supported cellular bone trabeculae as well as spherical cementum-like calcified deposits. This framework is interspersed with spaces lined by fibrovascular tissue supporting eosinophilic osteoid, consistent with traumatic bone cysts. <h3>Discussion</h3> COD lacks genetic abnormalities noted in fibrous dysplasia or neoplastic fibro-osseous lesions. We present an unusual association of COF with florid COD. This association has been previously reported in a patient who developed COF with COD and odontoma, and in another who developed peripheral osteoma, odontoma, COF and COD [2,3]. To the best of our knowledge, this presentation describes only the third case report of the association of COF and COD. The co-existence of COF and COD in these cases is unclear, but seems to be very rare.