Esthetic orthodontic archwires (fiber reinforced composite archwires) are
considered as the latest addition to orthodontic's world, and the load deflection rate is thought to be the
most important mechanical property of archwires which has strong e
ffect clinically, and this property is
affected by the cross section diameter and the material's type, for these reasons this study aims to
investigate the effect of the material's type and the cross section diameter of orthodontic archwires on the
load deflection rate of fiber reinforced composite(FRC) archwires with a diameter of 0.014 inch and
0.016 inch which are suitable for the leveling and alignment stage, and to compare these new materials
with Nickel titanium(NiTi) archwires .
