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Updated: May 27, 2026
19:44
A Tactile Automated Passive-Finger Stimulator (TAPS)
Published on: June 3, 2009
Active and passive self-ligation: a myth? Part 1: torque control.
Lorenz Martin Brauchli1, Markus Steineck, Andrea Wichelhaus
1Orthodontic Department, University of Basel, Basel, Switzerland. lorenz.brauchli@unibas.ch
The Angle Orthodontist
|November 9, 2011
Summary
Slot dimensions significantly impact torque expression in self-ligating brackets, more so than active clip designs. The spring clip
Area of Science:
- Orthodontic Mechanics
- Biomaterials Science
Background:
- Self-ligating brackets are widely used in orthodontics.
- Understanding torque expression is crucial for effective treatment.
Purpose of the Study:
- To quantify torque in various self-ligating brackets.
- To assess the impact of active clip designs on torque.
Main Methods:
- Measured torque moments for nine bracket types with a stainless-steel archwire.
- Evaluated active brackets in open and closed configurations.
- Optically measured slot dimensions and correlated with torque.
Main Results:
- Observed torque moments ranged from 3.1 to 22.6 Nmm at 30° angulation.
- Active spring clips contributed approximately 1 Nmm of torque.
- Most brackets achieved 10 Nmm torque at 20°-25° angulation.
Conclusions:
- Slot dimensions are the primary determinant of torque transmission.
- The influence of self-ligating mechanisms on torque is minimal.
- Active spring clip torque is significantly less than recommended values.
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