Cemento-ossifying fibroma of mandibular gingiva: single case report.

We report a case of a woman presenting a giant cementoossifying fibroma depending of the mandibular gingivae. The evolution of the process was 20 years. Cemento-ossifying fibroma is a relatively rare tumour classified between fibroosseous lesions. This lesion appears within the bone although in some occasions it involves the gingivae soft tissues, as the case we present. It is a slow-growing and well-defined tumorous lesion, because of this, it is considered as a benign lesion. The histologic findings alone may be similar to other pathologies such as osteoblastoma, low-grade osteosarcoma and particularly to fibrous dysplasia. An accurate diagnosis requires careful clinical, radiological and histological correlation in order to make an optimal treatment and an excellent outcome.