Abstract: An orthodontic arch wire is curved in two substantially perpendicular planes, one plane of curvature corresponding to the plane of the normal dental arch, the other plane perpendicular to this. By means of the compound curve arch wire, gentle and consistent pressure can be applied to all teeth in the dental arch simultaneously. These forces are applied through comparatively long lever arms in the appliance. Treatment time is significantly reduced and better cellular response is promoted. The arch wire is pre-looped for space closing and to facilitate attaching elastics.