In Vitro Comparison of Friction Generated by Various Models of Self-Ligating and Conventional Brackets while Performing Retraction with Sliding Mechanics
Introduction: In vitro studies suggest that certain variables such as friction coefficient, archwire size and force decay affect the effectiveness of sliding mechanics. To maximize the efficiency of sliding mechanics one should seek to control these variables. Objective: This in vitro study aimed to compare frictional forces in several models of self-ligating brackets, conventional systems, as well as different ways to tie the wire to the brackets during a simulation of sliding mechanics using 0.019″X0.025″ stainless steel wire. Material and methods: The study evaluated the levels of dynamic and static friction in six different types of brackets and three different ligation systems were used with conventional brackets: elastomeric modules, unconventional elastomeric ligature low friction system, and 0.20mm stainless steel-ligature. Results: The results showed that for both static and dynamic friction all other ligating systems exhibited statistically less friction than Gemini brackets with conventional elastomeric. Systems with lower levels of friction were as follows: SmartClip (E 0.08N; D 0.00N), Gemini brackets with Leone ligature (E 0.08N; D 0.04N), and Vision LP (E 0.04N; D 0.00N). Conclusion: During sliding mechanics frictional forces generated by the conventional ligation system were significantly higher than the forces generated by self-ligating brackets and other ligation systems.
