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Updated: Jun 17, 2026
11:17
Synthesis of Programmable Main-chain Liquid-crystalline Elastomers Using a Two-stage Thiol-acrylate Reaction
Published on: January 19, 2016
[Relaxation of an elastomeric chain under constant elongation]
Practica Odontologica
|June 1, 1990
Summary
This study investigated elastomeric chains, finding significant force relaxation within 24 hours. Pre-elongation reduced force decrease but increased residual force magnitude in orthodontic chains.
Area of Science:
- Orthodontic materials science
- Biomaterials engineering
Context:
- Elastomeric chains are crucial in orthodontics for applying continuous force.
- Understanding material behavior under physiological conditions (37°C saline) is vital for treatment efficacy.
- Power Chain II (Ormco Co) was selected for its common use in orthodontic applications.
Purpose:
- To evaluate the force degradation and relaxation characteristics of a specific elastomeric chain (Power Chain II) under various conditions.
- To compare the effects of pre-elongation and chain length (3 or 4 links) on force decay over one month.
- To quantify the initial force, and force at 24 hours, 1 week, and 1 month.
Summary:
- All tested elastomeric chains exhibited substantial force relaxation, averaging 52.85% after 24 hours.
- Pre-elongated chains showed a lower decrease in residual force compared to non-pre-elongated chains.
- However, non-pre-elongated chains retained a larger overall residual force magnitude at the study's end.
Impact:
- Findings provide critical data for orthodontists selecting and applying elastomeric chains, influencing treatment planning and patient outcomes.
- This research contributes to the understanding of long-term force stability in orthodontic appliances.
- Highlights the trade-off between reduced force decay and retained force magnitude based on pre-elongation.
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