Kit for a self-modellable and customisable device for teeth and mouth； the kit comprising: - a device (1, 1') for teeth and mouth configured to be housed inside a user's mouth coupled to a dental arch； the device (1, 1') being U-shaped for coupling to a dental arch and comprising two lateral arms (2, 3) and a connecting frontal portion (4)； the device (1, 1') comprising at least one invitation to cut (5) at each lateral arm (2, 3)； and - a gripping device configured to be coupled in a releasable way to the device for teeth and mouth (1, 1')； wherein the gripping device (17) comprises a plurality of coupling portions (18, 19, 20) with the device for teeth and mouth (1, 1')·
