Evaluation of friction on self-ligating and conventional brackets associated with different types of archwires submitted to sliding mechanics

• Published in: Brazilian journal of oral sciences Vol. 18; p. e191605
• Main Authors: Barbosa, William Carlos Silva, Correr, Américo Bortolazzo, Carneiro, Diego Patrik Alves, Vedovello Filho, Mário, Godoi, Ana Paula Terossi de, Valdrighi, Heloísa Cristina
• Format: Journal Article
• Language: English
• Published: Universidade Estadual de Campinas 12-11-2019
• Subjects: Friction; Orthodontic appliance design; Orthodontic brackets
• ISSN: 1677-3225; 1677-3225
• DOI: 10.20396/bjos.v18i0.8657258

Aim: The aim of this study was to verify the frictional force during sliding mechanics in orthodontic tooth movement, using conventional metal brackets of the active and passive self-ligating types with stainless steel and copper nickel titanium archwires. Methods: This experimental in vitro study was conducted with conventional metal (Morelli, Sorocaba, SP, Brazil) brackets, active self-ligated (SLI Morelli, Sorocaba, SP, Brazil) and passive self-ligated (SLP Morelli, Sorocaba, SP, Brazil), with slot 0.022 x 0.028 inches and Roth prescription.  The brackets were tested with rectangular section 0.019 x 0.025 inch copper nickel titanium and stainless steel archwires. For each type of bracket, 10 sets of plate/bracket/archwire segment (n=10) were fabricated. Non-parametric Kruskal Wallis and Dunn tests were used for comparison between types of brackets and Wilcoxon tests for comparison between types of archwires. Results: The results showed that the frictional force values were higher with copper nickel titanium than with stainless steel archwires (p<0.05). When copper nickel titanium archwires were used, the active self-ligating brackets showed higher frictional force values than the other types, followed by the conventional brackets.  Lower frictional force values were observed with passive self-ligating brackets. For stainless steel archwires, no difference was observed between conventional and active self-ligating brackets, the passive self-ligating type presented lower frictional force values than the others. Conclusion: It was concluded that the higher frictional force was observed when active self-ligating brackets were associated with copper nickel titanium archwires.  Lower frictional force was verified between passive self-ligating brackets combined with stainless steel archwires.