Frictional resistance between orthodontic brackets and archwires in the buccal segments

Abstract Orthodontic sliding mechanics using preadjusted brackets is a popular approach for achieving incisor retraction. A distally directed force slides the archwire through brackets and tubes in the buccal segments. Friction in the buccal segments contributes resistance to the force required to achieve tooth movement, and techniques to reduce friction reduce the potential for anchorage loss. This in vitro study used an lnstron testing machine to assess frictional forces for three types of 0.022 × 0.028 inch brackets: preadjusted stainless steel premolar brackets (Standard Straight Wire, “A” Company, Inc, San Diego, Calif), Activa brackets (“A” Company Inc, San Diego, Calif), and Speed brackets (Strite Industries Ltd), combined with five wire sizes (0.018, 0.020, 0.016 × 0.022, 0.018 × 0.025 and 0.019 × 0.025 inch). A model with one attached molar bracket and one or two premolar brackets simulated the buccal segments. Activa brackets produced the least friction for all wires tested. Speed brackets with ...