English

Abstract

Osteochondroma / osteocartilagenous exostosis is a cartilage-capped exophytic lesion that arises from the cortex of bone. It constitutes 20 - 50% of all benign tumours and 10 - 15% of all bone tumours, but it is actually a developmental lesion rather than a true neoplasm. An osteochondroma in the maxillo- facial region, however, is rare. In this anatomical area, the tumour is most often reported in association with the coronoid process. Osteochondroma of the mandibular condyle is rare and only 37 documented cases have so far been reported in the English language literature. I report a case of osteochondroma of the mandibular condyle and describe the characteristic OPG and CT features of this condition. INTRODUCTION: Osteochondroma (OC) of the mandibular condyle is a relatively rare condition that causes a progressive enlargement of the condyle, usually resulting in facial asymmetry, temporomandibular joint (TMJ) dysfunction, and malocclusion. Radiographically, there is a unilaterally enlarged condyle usually with an exophytic outgrowth of the tumor from the condylar head. I present a case of a left mandibular condylar OC that created a malocclusion, and TMJ Dysfunction. lesion was fairly well circumscribed with thin cortex. Left mandibular condyle was not seen separately. The patient was adviced CT scan for further evaluation. Saggital and coronal CT images revealed a large globular, mixed bone density condylar mass arising from left mandibular condyle (Figures 2 and 3). The lesion was extending superiorly into the articular fossa, but the cortical bone of the fossa was intact. The cortex of the tumor was continuous with that of the normal condylar bone. The pattern of the trabecular bone of the tumor blended with the intramedullary host bone. There was an evidence of pseudoarthosis formation with greater wing of sphenoid bone with thinning of greater wing. The lesion was reaching up to pterygoid process with compression and thinning of pterygoid process. Mandibular condyle was displaced laterally by the lesion. Tumor excision was performed. Histopathologic examination revealed a nodular lesion having cartilaginous cap and mature bone tissue beneath, consistent with osteochondroma. DISCUSSION: Osteochondroma is a benign tumour of the appendicular skeleton arising from the metaphyseal regions of long bones, most commonly seen in the second and third decade of life. Osteochondromas are not common in the mandibular condylar region. Review of the literature indicates that patients with these tumours present mainly in the fourth decade with mean age of 39.7 years and a male to female ratio of 1:1.5. Clinical findings associated with osteochondroma of