Bilateral arteriovenous malformation of the mandible.

Spontaneous bleeding from the molar gingiva may reflect the presence of a life-threatening vascular malformation. Sporadic reports of exsanguinating hemorrhage in the dental literature warn of the dangers of extraction, although deaths from unrecognized lesions or secondary to mandibular fracture still occur. Arteriovenous malformation (AVM) may be either unilateral or, less commonly, bilateral, and should be suspected in individuals with large lower facial hemangiomata. Two cases of near-exsanguinating hemorrhage from bilateral AVMs are discussed with the long-term management over a 3- to 20-year follow-up. The report underscores the failure of therapeutic embolization and the need for computed tomographic scanning as a corollary to angiography. A newer treatment with direct removal of the AVM and obliteration methods solves the hemorrhagic complications, reduces the potential for steal syndromes, and reduces the potential for recurrence.