Evaluation and comparison of frictional forces generated by three different ligation methods (An in vitro study)

Abstract

Background: This study aims to evaluate and compare the static and kinetic frictional forces produced by a passive self-ligating bracket (SLB) and a conventional stainless steel bracket (CB) ligated with two different ligation methods when used with two types of wires. Materials and Method: The brackets, wires and ligation methods used in vitro were a passive SLB and a CB ligated with two different ligation methods (stainless steel ligature wire [SSLW] and conventional figure "O" elastomeric ligature [CEL]). The bracket ligation systems were tested with two types of wires (0.014" nickel titanium wire and 0.019" × 0.025" stainless steel wire). Resistance to sliding of the bracket/wire/ligature systems was measured with an experimental model mounted on the crosshead of an Instron testing machine with a 10 N load cell. Each sample was tested 10 consecutive times under a dry state. Results: Frictional forces close to 0 gm were recorded in all tests with SLB with both wire types. Resistance to sliding increased significantly (18-38 gm) (P < .05) when SSLW on CB was used with both wires and (84-104 gm) (P < .05) when CEL on CB was used with both wires. Conclusion: SLB is able to produce statistically high significant lower frictional forces compared with SSLW and CEL, while SSLW is able to produce statistically high significant lower frictional forces compared with CEL.