Abstract: The arch wire of an orthodontic appliance is received in the channel of a bracket fixed to each of a patient's teeth to be repositioned. Each bracket includes a holder in which is removably located a selected one of a set of channel members, the channels of which are differently inclined to provide a selection of different force vectors to be introduced by the arch wire on the teeth. The holder is separable from the bracket base and is movable relative thereto to permit tipping the arch wire channel and changing its related height between the gingival and occlusal ends of the tooth, and means are provided which releaseably lock the holder in an adjusted position to the bracket base.