An arm construction of an intra-oral x-ray device according to the present invention comprises at least two elongated support arms (55, 56, 55′, 56′) jointed to each other, into connection with a substantially first end of the first support arm (55) of which is arranged a radiation source (4) and in which the jointing between the support arms is implemented such that the successive support arms (55, 56, 55′, 56′) connect to each other from sides (68, 69) of the support arms facing each other.
