Aneurysmal bone cysts of the jaws.

Two cases of aneurysmal bone cyst are recorded. In the first there is clinical evidence to suggest that the lesion had been present for an unusually long period while incomplete clinical records of the other also indicate an unusual history. Histologically both lesions show a paucity of giant cells. It is not possible to make significant observations on aetiology other than support the theory that the lesion arises as a result of altered haemodynamics.