This in vitro study measured the force-deflection behavior of selected initial alignment archwires by conducting three-point bending tests under controlled conditions. The study tested four wire designs: multistranded stainless steel, conventional stainless steel, superelastic nickel-titanium, and thermoactivated nickel-titanium archwires.The wires (n = 15) were ligated into stainless steel brackets with steel ligatures. A testing machine recorded deactivations at 2.0 mm of deflection at 37 degrees C. Force-deflection measurements were recorded from only deactivation. Forces on deactivation were compared by one-way analysis of variance (ANOVA) and Tukey post-hoc tests.Significant differences (P .05).Both nickel-titanium and multistranded steel archwires tested are potentially adequate for use during the leveling and aligning phase of orthodontics.