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Updated: Mar 27, 2026
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Force System with Vertical V-Bends: A 3D In Vitro Assessment of Elastic and Rigid Rectangular Archwires
Published on: July 24, 2018
11.4K
Segmental torque relevant orthodontic bracket tie-wing deformation in various bracket-archwire-ligature combinations
Subramanian Sundar1, Pandurangan Harikrishnan2, Devadhas Kingsly Jeba Singh1
1Department of Mechanical Engineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, India.
Summary
This study investigated torque moments in orthodontic brackets, finding that larger archwire dimensions and rotations increase torque. Stainless steel ligatures produced significantly higher torque than elastic ligatures, impacting tooth positioning.
Area of Science:
- Orthodontics
- Biomaterials Science
- Dental Mechanics
Background:
- Torque moments are crucial in fixed appliance therapy for achieving final tooth positions.
- Previous research focused on single bracket-archwire interactions, neglecting clinical use of segmental torque.
Purpose of the Study:
- To analyze torque moments and tie-wing deformation in 2-bracket segments under various clinical conditions.
- To evaluate the influence of archwire dimensions, rotation, ligation type, and interbracket distance (IBD) on torque.
Main Methods:
- Experiments utilized 0.018-in and 0.022-in conventional brackets with rectangular archwires and ligatures.
- Torque moment and tie-wing deformation were measured across 6, 7, and 8 mm interbracket distances.
Main Results:
- Torque moment increased with larger archwire dimensions and greater archwire rotation.
- Stainless steel ligatures generated significantly higher torque than elastic ligatures.
- Distal and mesial tie-wing deformations differed significantly across tested combinations.
Conclusions:
- The 2-bracket segment-archwire-ligature combination's behavior is significantly influenced by individual factors and their interactions.
- Understanding these factors is essential for optimizing torque control in orthodontic treatment.
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