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Colourimetric changes experienced in three types of aligners according to the L'Eclairage Commission
Teresa Domingo-Jiménez1, María José González-Olmo1, Carolina Nieto-Moraleda1
1Department of Orthodontics, University Rey Juan Carlos, Alcorcón, CP 28922, Madrid, Spain.
European Journal of Orthodontics
|September 30, 2024
Summary
Invisalign® aligners showed significant color changes in coffee, becoming darker, redder, and more yellow. Spark® aligners also changed color in water and coffee over seven days.
Area of Science:
- Dental Materials Science
- Orthodontics
- Colorimetry
Background:
- Clear aligners are widely used in orthodontic treatment.
- Understanding material stability and color change is crucial for patient satisfaction.
- Different aligner brands may exhibit varying responses to staining agents.
Purpose of the Study:
- To compare the colorimetric changes (L*, a*, b*) of three aligner brands (Invisalign®, Spark®, QuickSmile®) when exposed to coffee and distilled water.
- To evaluate the initial colorimetric characteristics of these aligner types.
Main Methods:
- 120 aligners (40 each of Invisalign®, Spark®, QuickSmile®) were tested.
- Aligners were immersed in distilled water or coffee.
- Spectrophotometry was used to measure color at baseline, 12 hours, and 7 days.
- Color changes (ΔE*) were calculated and analyzed statistically.
Main Results:
- Initially, Invisalign® and Spark® were redder, QuickSmile® greener; all tended towards yellow, with Invisalign® least so.
- In water, Spark® showed noticeable changes after 7 days; Invisalign® and QuickSmile® showed slight changes.
- In coffee, Invisalign® exhibited significant color shifts (darker, redder, yellower) within 12 hours and 7 days; Spark® showed appreciable changes by 7 days.
Conclusions:
- Invisalign® aligners initially have a redder, less yellow hue.
- Spark® aligners demonstrated noticeable color changes in water over 7 days.
- Coffee significantly impacts Invisalign® color, causing darkening and shifts to red and yellow hues, highlighting the need for patient awareness.
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