Craniostat (20) for an extraoral dental radiographic apparatus (1), comprising a chin rest (52), a bite (54), both of which optionally removable, said bite (54) has centring surfaces having a predefined orientation with respect to a centring position of the bite itself, the bite being blocked in the blocking position through the tightening of said surfaces against tightening surfaces also having a predefined orientation with respect to a bite centring position, so that in tightened condition the bite (54) is also automatically brought in the correct centring position on the sagittal plane.Moreover, a method of use of the craniostat is described.
