Ameloblastoma

This video shows the resection of a large mandibular ameloblastoma. The extirpation of the tumor required a segmental mandibulectomy with concomitant mandibular & inferior alveolar nerve reconstruction.
This tumor emanates from the odontogenic epithelium. It is associated with tooth root resorption on x-ray. Besides odontoma, ameloblastoma is the most frequent odontogenic tumor. They may originate from cell rests of the enamel organ, from a developing enamel organ, from the epithelial lining of an odontogenic cyst, or from the basal cells of the oral mucosa. Radiologically, ameloblastoma may show root resorption of the teeth; however, this is not pathognomonic. Clinically, these tumors may be compared to basal cell carcinomas of the skin. Biopsy must be performed for definitive diagnosis. The high rate of recurrence justifies the resection of the involved bone, as the actual margin of the tumor often extends beyond its radiological or clinical margin. With this point in mind, radical segmental resection via an extraoral approach is mandatory. In most cases, reconstruction of mandibular continuity is possible with a non-vascularized bone graft from the iliac crest. The nerve graft is positioned laterally to the bone graft to facilitate later implant placement. Free tissue transfer is only required in the event of a previous failed bone graft or in cases where extremely large bone defects are created. In this case, there was infiltration of the soft tissues of the oral cavity, which likewise required resection & intraoral reconstruction. Rare cases may metastasize to the lungs or neck. Only 20% involve the maxilla & these are generally more aggressive.