AFD and AFO presented several similarities: higher prevalence in men and in the mandibles, similar mean age of patients, rate of cortical bone perforation and of the lesions' association with displaced or unerupted teeth and tooth root resorption, mean lesion size, and recurrence rate. The lesions differed in the presence of radiopacities and locularity. Taken together, these data do not support the concept of progressive maturation of these tumoral conditions.