Clinical and diagnostic findings of Paget's disease of the jaws are reported; up to date etiological and pathogenical hypotheses are presented. Laboratory data of increased P.A. as a marker of disease evolution is pointed out, particularly the relationship increasing hydroxyprolinuria, because the increase of a malignant transformation. Surgery, always modeling, is limited to cases of severe facial dysmorphosis associated or not with the local disturbance due to compression; in any case it is suggested to perform the surgery in the phases of inactivity of disease, to avoid local complications, such as hemorrhage a infection.