The optic neuropathy due to dental affection is rare but functionally serious. Authors report four cases of patients who have an acute dental infection with unilateral inflammation of the optic nerve. The first symptom was in all cases a sudden fall of visual acuity. The visual field is always altered. Papilloedema is observed in three eyes. The treatment is of the dental infection at first, secondly, corticosteroïds are associated. An improvement is noticed in three cases. The authors discuss the physiopathology of the affection, its symptoms and treatment.