Wegener's granulomatosis or granulomatosis with polyangiitis (GPA) is a disease characterized by inflammation and necrosis of the blood vessel walls. It is of unknown etiology, low prevalence and high degree of aggressiveness. This disease can compromise the oral tissues, causing enlargement and inflammation of the gingival tissues. The case of a male patient who presented rapidly growing gingival tissue enlargement and inflammatory characteristics associated with the diagnosis of Wegener's granulomatosis is reported. The lesion was removed surgically and the diagnosis was achieved by combining the serological findings of the ANCA test, periodontal manifestations and histopathological analysis of the lesion. The patient was treated with methotrexate and corticosteroids and the lesion did not reappear after 2 years of control. In this article, the periodontal manifestations associated with GPA are analyzed, highlighting the importance of an adequate diagnosis of periodontal lesions characterized by gingival enlargement and inflammation.