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Updated: Aug 8, 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
Forces released during alignment with a preadjusted appliance with different types of elastomeric ligatures
Lorenzo Franchi1, Tiziano Baccetti
1Department of Orthodontics, University of Florence, Florence, Italy. l.franchi@odonto.unifi.it
Summary
New nonconventional elastomeric ligatures (NCEL) generated significant forces during canine misalignment, unlike conventional elastomeric ligatures (CEL) which produced minimal force at 4.5 mm or more. This comparison aids orthodontic treatment planning.
Area of Science:
- Orthodontics
- Biomaterials Science
Background:
- Elastomeric ligatures are crucial in orthodontic treatment for leveling and aligning teeth.
- Comparing the force delivery of new nonconventional elastomeric ligatures (NCEL) and conventional elastomeric ligatures (CEL) is essential for optimizing treatment outcomes.
Purpose of the Study:
- To quantitatively compare the forces generated by NCEL and CEL during simulated leveling and aligning phases in orthodontics.
- To evaluate the efficacy of NCEL in delivering consistent forces across various wire sizes and degrees of canine misalignment.
Main Methods:
- An in-vitro testing model utilized stainless steel brackets and superelastic nickel-titanium wires of varying sizes (0.012-, 0.014-, 0.016-in).
- Forces were measured with NCEL and CEL at different vertical positions simulating canine misalignment (1.5, 3, 4.5, and 6 mm).
Main Results:
- Significant differences in force generation were observed between CEL and NCEL for most tested variables (P <.01).
- NCEL consistently produced noticeable forces (50-150 g) across all canine misalignment levels and wire sizes.
- CEL generated approximately zero force at 4.5 mm or greater canine misalignment.
Conclusions:
- NCEL demonstrate superior force delivery capabilities compared to CEL, particularly in managing significant canine misalignments.
- The findings suggest NCEL may offer improved efficiency in orthodontic leveling and aligning phases.
- Further clinical studies are warranted to validate these in-vitro findings.
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