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Introduction: The search for more aesthetic and comfortable orthodontic devices has led to an increase in the use of clear aligners. Objective: To increase knowledge on biological mechanisms of orthodontic tooth movement using Invisalign aligners. Methods: This study included 11 patients with a mean age of 23.6 ± 4.8 years. Cases planning included alignment and leveling of lower incisors using Invisalign aligners. Gingival crevicular fluid samples were collected from the lower incisors on the day of delivery of aligner number 1 (T0) and after 1 (T24h), 7 (T7d), and 21 (T21d) days. During the observation period of the study, the patients used only the aligner number 1. Levels of nine cytokines were quantified using Luminex’s multi-analysis technology. Non-parametric tests were used for comparisons between cytokine expression levels over time. Results: Cytokine expression levels remained constant after 21 days of orthodontic activation, except those of MIP-1β, which presented a statistical difference between T24h and T21d with a decrease in the concentration levels. IL-8, GM-CSF, IL-1β, MIP-1β, and TNF-α showed the highest concentrations over time. Conclusions: The different behavior in the levels of the investigated cytokines indicates a role of these biomarkers in the tissue remodeling induced by Invisalign.

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Objective: The aim of the present study was to evaluate the color stability of Filtek Z350 XT, Filtek Z250 XT, Z100 resin composites and Transbond XT orthodontic resin, all used in orthodontic attachments, when immersed in popular beverages. Methods: Thirty disk-shaped specimens of each resin composite (2 x 5mm) were manufactured and randomly divided into six groups according to immersion solutions: coffee, red wine, white wine, regular beer, dark beer and deionized water (control). The specimens were fully immersed in each of the solutions for six days at 37°C, representing approximately six months of consumption. The color measurements were evaluated by a reflection spectrophotometer, at baseline (before immersion) and after staining. L*a*b* coordinates were measured and the color change (ΔE00) was calculated using the CIEDE2000 formula. The data were analyzed by ANOVA/Tukey tests at a significance level of 0.05. Results: The resin composites immersed in white wine and regular beer showed either imperceptible or clinically acceptable ΔE00, and no difference from the control group (p= 0.4449 and p= 0.467 respectively). Immersion in coffee and red wine were considered clinically unacceptable and were significantly different from the control group (p= 0.0028 and p= 0.0475 respectively). Conclusion: Based on the results of the present study, the consumption of coffee and red wine may cause color change of the resin composite attachments above the visual acceptability threshold, and impair aesthetics during treatment.