Static frictional resistances were compared between Teflon-coated stainless steel and clear elastomeric ligatures used with various combinations of brackets and archwires. Stainless steel metal, polycrystalline ceramic and single crystal ceramic 0.022-inch slot brackets were used in combination with stainless steel and nickel titanium archwires, 0.01 8 inch and 0.01 6 ×0.022 inch. Friction was measured in the dry state at bracket-archwire angulations of 0, 5, 10, and 15 degrees. Moments induced by engagement of the archwires into the brackets were measured for each archwire type and bracket-archwire angulation. Teflon-coated ligatures produced less friction than elastomers for all bracket-archwire combinations. The ceramic brackets generally elicited greater frictional resistances than stainless steel brackets. Regarding both friction and control of tooth movement, these data suggest that sliding mechanics are best executed with stainless steel brackets and stainless steel archwires. Moreover, these data reveal the usefulness of Teflon-coated ligatures in minimizing the high friction of ceramic brackets when an esthetic appliance is imperative.
D.J. De Franco is in private orthodontic practice in Milan, Italy, and was an Assistant Professor in the Department of Orthodontics at the Harvard School of Dental Medicine
R.E. Spiller is a Major in the U.S. Army Dental Corps at Fort Knox, Kentucky
J.A. von Fraunhofer is a Professor in the Department of Biological and Biophysical Sciences at the School of Dentistry, University of Louisville