An archwire for use with a passive self-ligation orthodontic bracket is described and which includes a resilient main body which is received in the archwire slot, and which further has a predetermined width dimension, and a variable thickness dimension, and wherein the variable thickness dimension of the archwire can be varied so as to facilitate an adjustable application of a force to the passive self-ligation orthodontic bracket so as to achieve a clinician selectable and controllable second and third order movement of a patients tooth.
