Comparison of friction among low-friction ligation, conventional ligation and self ligation with conventional stainless steel and esthetic brackets – an in vitro study

Abstract

BackgroundAmong the numerous factors affecting friction between the bracket-archwire interface, the method of ligation is one of the most important. A number of ways have been proposed to reduce this friction, including self-ligating brackets and more recently Slide™ (Leone SpA, Firenze, Italy) low-friction ligatures. This study aims to compare the frictional forces generated by three different ligation methods; conventional ligation, self ligation and Slide low-friction ligation, using metallic and ceramic brackets. Materials and methodsThree models with 10 aligned brackets (standard, self-ligating and ceramic) were used with conventional and low-friction ligatures to study the frictional resistance generated with 0.016″ Nitinol (NiTi) and 0.019 × 0.025″ Stainless steel (SS) wires. ResultsConventional ligation produced the greatest friction regardless of wire or bracket combination used. With smaller round wires, the self-ligating system exhibited less friction than low-friction ligation and with higher dimension archwires it exhibited greater friction. Slide low-friction ligatures were able to reduce the friction of ceramic brackets in a similar way to stainless steel brackets. ConclusionSlide low-friction ligatures produced a reduction in friction with both metallic and ceramic brackets to a level comparable to that of self-ligating brackets.