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Force Degradation of Elastomeric Chains after Storage Time and Mechanical Brushing
Antonio Carlos da Silva Chaves-Filho1, Ana Rosa Costa1,2, Lincoln Pires Sousa Borges2
1Department of Orthodontics, Graduate Program in Orthodontics - UNIARARAS, Universidade de Araras, SP, Brazil.
Brazilian Dental Journal
|November 17, 2021
Summary
Orthodontic elastomeric chain force significantly decreases over time and after mechanical brushing. Morelli and 3M Unitek chains maintained higher force, while GAC had the lowest, indicating variable long-term performance.
Area of Science:
- Orthodontics
- Biomaterials Science
- Dental Materials
Background:
- Elastomeric chains are crucial in orthodontic treatment for applying continuous force.
- Understanding the force decay of these chains over time and under simulated oral conditions is vital for treatment efficacy.
Purpose of the Study:
- To evaluate the force decrease of different orthodontic elastomeric chains.
- To compare force decay at various time points: initial, 10 minutes, 1 day, 28 days, and after mechanical brushing.
Main Methods:
- In vitro study using twenty segments of four commercial elastomeric chain brands.
- Force measurements using an Instron universal testing machine at specified intervals.
- Simulated mechanical brushing using the MSCT 3 machine.
Main Results:
- All tested elastomeric chains exhibited a statistically significant reduction in force after 1 day, 28 days, and mechanical brushing (p<0.05).
- Morelli and 3M Unitek chains consistently delivered significantly higher force compared to Abzil and GAC after 1 day, 28 days, and mechanical brushing (p<0.05).
- GAC elastomeric chains demonstrated the lowest force retention.
Conclusions:
- The force delivered by all evaluated elastomeric chains decays rapidly over time.
- Morelli and 3M Unitek brands offer superior force maintenance compared to Abzil and GAC, especially after simulated mechanical wear.
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