The aim of our study was to prove whether the galvanic cell in the mouth is able to influence the disease course in the recurrent aphthous ulcer (RAU). For this purpose on the basis of informed consent and in agreement with the Helsinki Declaration the group of thirty-six patients with RAU and amalgam as the only dental material used in the mouth was clinically examined. The galvanic currents were measured as well. In twelve patients the pathological values of galvanic currents were found and the electro-active amalgam fillings were removed. We followed the clinical course of the disease: the frequency of recurrences, number and size of aphthous ulcers - at least half a year before and half a year after the intervention. Ten treated patients (83.3 %) showed improvement of their health in sense of reduction of recurrence number and lesions number or the decrease of ulcer area. We conclude that galvanic cell is able to influence negatively both the frequency of recurrence and the number of ulcers and partly also the size of the ulcers and in such a way it affects the way of healing. That is the reason why we recommend to the patients with aphthous stomatitis to do the measurement of galvanic currents in the mouth and in case of pathologic values to use the removal of electro-active dental restorations as one of the treatment tools.

        Key words: recurrent aphthous ulcer - galvanic cell - electro-active amalgam replacement - treatment effect