Pulp necrosis or unsuccessful endodontic treatment may be a painful process or be completely asymptomatic, regardless of their radiographic features. However, there is no report in the literature regarding the presence of an early sign of pulp necrosis preceding pulpal pain, incomplete endodontic fillings or radiographically complete endodontic fillings performed under unsterilized conditions. In this case series, we described four cases who had a common complaint of itching gingiva. The gingival itching, from which they suffered, disappeared after performing/redoing the endodontic treatment. Thus, itching gingiva may be an early sign of pre-inflammatory pulp necrosis or unsuccessful endodontic treatment.