Chondroblastic Variant of Osteosarcoma of Mandible: Report of a Rare Case.

Osteosarcoma (OS), a common malignant tumour of the long bones, is rarely seen in the craniofacial region (5-8%). Though it's aetiology is unknown, previous radiotherapy, Pagets disease, Retinoblastoma and benign bone lesions such as fibrous dysplasia are considered as predisposing factors. It is seen commonly in adults between the third and fourth decades of life, in the Gnathic location mandible.