The Effect of Various Ligation Methods on Friction in Sliding Mechanics

Aim: To evaluate the effect of ligation method on friction and the efficacy of the new slick elastomeric modules (TP Orthodontics, USA) and slide elastomeric modules (Leone Orthodontics, Italy) which claim to reduce friction at the module/wire interface. Materials and methods: Slick and slide modules were compared with regular modules, modules tied in figure of eight fashion, tight stainless steel ligatures, and loose stainless steel ligatures. Brackets used for the study were 0.022" × 0.028" maxillary first premolar twin brackets (MBT Prescription, Gemini series, 3M Unitek USA.) The effect of bracket width on friction produced with four different methods of ligation was also studied using 0.022" × 0.028" maxillary first premolar single width brackets (Alexander prescription, Leone Co. Italy). Results: When considering tooth movement along a 0.019" × 0.025" in stainless steel archwire, Super slick module produce less friction when compared to regular module, module tied in ‘figure of 8’ pattern and tight SS ligation produced more friction when compared to loose SS ligation and slide module. Slide modules produce least friction when compared to other available methods of ligation. Modules tied in a ‘figure of 8’ pattern generate highest friction. Conclusion: Slide modules produce least friction followed by loose SS ligation, slick modules, regular modules, tight SS ligation and highest friction was produced by regular modules tied in a ‘figure of 8’ pattern. Width of bracket had no influence on friction produced.