Tarek El-Bialy1,2,3, Ahmad Alobeid4, Cornelius Dirk4, Andreas Jäger5, Ludger Keilig4, Christoph Bourauel4. 1. Department of Orthodontics, School of Dentistry, University of Alberta, Edmonton, Canada. telbialy@ualberta.ca. 2. Oral Technology, School of Dentistry, University of Bonn, Bonn, Germany. telbialy@ualberta.ca. 3. 7-020D Katz Group Centre for Pharmacy and Health Research, University of Alberta, T6G 2E1, Edmonton, Alberta, Canada. telbialy@ualberta.ca. 4. Oral Technology, School of Dentistry, University of Bonn, Bonn, Germany. 5. Department of Orthodontics, School of Dentistry, University of Bonn, Bonn, Germany.
Abstract
AIMS: The aim of this study was to compare force loss due to friction (Fr) during simulated canine retraction using different archwire dimensions and materials between conventional and new self-ligating brackets. METHODS: The tested brackets were (1) conventional brackets (Victory series, GAC twin and FLI twin), (2) self-ligating brackets (Damon-Q, FLI-SL, new/improved FLI-SL (I FLI-SL), SPEED, GAC innovation (R) and Ortho Classic) and (3) a low-friction bracket (Synergy). All brackets had a 0.022″ slot size. The tested archwires were stainless steel (0.018″; 0.016″x0.022″; 0.017″x0.025″; 0.018″x0.025″ and 0.019″x0.025″); nickel titanium (NiTi; 0.016″x0.022″; 0.017″x0.025″; 0.018″x0.025″ and 0.019″x0.025″) and titanium molybdenum alloy (TMA; 0.016″x0.022″; 0.017″x0.025″; 0.018″x0.025″ and 0.019″x0.025″). Canine retraction was experimentally simulated in a biomechanical set-up using a NiTi coil spring that delivered a force of 1 N. The simulated retraction path was up to 4 mm. Force loss due to friction was compared between groups using the Welch t‑test. RESULTS: Force loss due to friction increased with increasing archwire size. Also, TMA showed the highest and stainless steel the lowest force loss due to friction. FLI-SL brackets showed the lowest Fr (31%) and Ortho Classic showed the highest (67%). CONCLUSIONS: Increasing wire size generally showed increasing force loss due to friction. FLI-SL brackets showed the lowest, while Ortho Classic showed the highest friction.
AIMS: The aim of this study was to compare force loss due to friction (Fr) during simulated canine retraction using different archwire dimensions and materials between conventional and new self-ligating brackets. METHODS: The tested brackets were (1) conventional brackets (Victory series, GAC twin and FLI twin), (2) self-ligating brackets (Damon-Q, FLI-SL, new/improved FLI-SL (I FLI-SL), SPEED, GAC innovation (R) and Ortho Classic) and (3) a low-friction bracket (Synergy). All brackets had a 0.022″ slot size. The tested archwires were stainless steel (0.018″; 0.016″x0.022″; 0.017″x0.025″; 0.018″x0.025″ and 0.019″x0.025″); nickel titanium (NiTi; 0.016″x0.022″; 0.017″x0.025″; 0.018″x0.025″ and 0.019″x0.025″) and titanium molybdenum alloy (TMA; 0.016″x0.022″; 0.017″x0.025″; 0.018″x0.025″ and 0.019″x0.025″). Canine retraction was experimentally simulated in a biomechanical set-up using a NiTi coil spring that delivered a force of 1 N. The simulated retraction path was up to 4 mm. Force loss due to friction was compared between groups using the Welch t‑test. RESULTS: Force loss due to friction increased with increasing archwire size. Also, TMA showed the highest and stainless steel the lowest force loss due to friction. FLI-SL brackets showed the lowest Fr (31%) and Ortho Classic showed the highest (67%). CONCLUSIONS: Increasing wire size generally showed increasing force loss due to friction. FLI-SL brackets showed the lowest, while Ortho Classic showed the highest friction.
Authors: Andrea Wichelhaus; Tena Eichenberg; Philip Gruber; Elias Panos Bamidis; Thomas Stocker Journal: Materials (Basel) Date: 2022-06-15 Impact factor: 3.748