Evaluation of torque moment in esthetic brackets from bendable alloy wires

• Published in: The Angle orthodontist 2021-09, Vol.91 (5), p.656-663
• Main Authors: Nakano, Taiji, Nakajima, Akira, Watanabe, Hiroto, Osada, Ayaka, Namura, Yasuhiro, Yoneyama, Takayuki, Tanaka, Eiji, Motoyoshi, Mitsuru
• Format: Article
• Language: English
• Subjects: Dentistry; Original
• ISSN: 0003-3219; 1945-7103
• DOI: 10.2319/081820-729.1

To examine the torque moment that occurs between esthetic brackets and bendable alloy (stainless steel [SS], titanium-molybdenum [Ti-Mo], and titanium-niobium [Ti-Nb]) wires. This study examined ceramic (CR), zirconium oxide (ZC), polycarbonate (PC), and conventional metallic brackets (MT) (upper, 0.018-inch and 0.022-inch slots) combined with SS, Ti-Mo, and Ti-Nb wires using elastic module ligation. The torque moments delivered by various wire and bracket combinations were measured using a torque gauge apparatus. The wire torque angles at 5-40° were examined. The torque value increased in the order of CR, ZC, MT, and PC brackets for both 0.018-inch and 0.022-inch slots. The fracture points of the CR and ZC brackets combined with SS and Ti-Mo wires were approximately more than 30° and 35°, respectively. No fracture points were detected in the combination of ZC brackets and Ti-Nb wires. The current study identified the material characteristics of CR, ZR, and PC brackets during torque tooth movements. The present results demonstrate a characteristic combined effect between different esthetic brackets and bendable alloy wires.