In vivo and in vitro color evaluation of clear thermoplastic retainers.
Creators: name: Ζαφειριάδης, Αναστάσιος Α.
Publisher: name: Aristotle University of Thessaloniki
Year: 2017
Subjects: Ορθοδοντική συγκράτηση
Αποχρωματισμός
Οδοντιατρικά υλικά
Χρωστικοί παράγοντες
Orthodontic retainers
Discoloration
Dental materials
Staining agents

description: Σκοπός ήταν να εκτιμηθεί η in vitro επίδραση διαφορετικών διαλυμάτων χρώσης στο χρώμα των ναρθήκων Vivera® και η in vivo μεταβολή του χρώματος δύο διαφορετικών θερμοπλαστικών ναρθήκων συγκράτησης, Vivera® και Essix® C+. Τριάντα ασθενείς μετά από ορθοδοντική θεραπεία τυχαιοποιήθηκαν σε δύο ομάδες και έλαβαν συγκρατητικούς νάρθηκες Vivera® και Essix® C+, αντίστοιχα. Τριάντα δείγματα υλικού Vivera® αποδόθηκαν σε πέντε ομάδες και βυθίστηκαν σε διαφορετικά χρωστικά διαλύματα. Για κάθε ένα από τα δείγματα μετρήθηκαν οι παράμετροι χρώματος CIE (L*, a*, b*) in vivo με φασματοφωτόμετρο SpectroShade™ Micro μετά από έως και 3 μήνες ενδοστοματικής χρήσης και in vitro με φασματοφωτόμετρο ορατού-υπεριώδους μετά από έως και μία εβδομάδα εμβάπτισης σε διάλυμα. Υπολογίστηκαν οι διαφορές χρώματος (ΔΕ) μεταξύ των ομάδων. Έγινε ανάλυση ANOVA του στατιστικού δείγματος και συγκρίσεις με τη μέθοδο Bonferroni. Δεν παρατηρήθηκαν in vivo σημαντικές διαφορές στη μεταβολή του χρώματος μεταξύ Vivera® και Essix® C+ στις μεταβολές ΔΕ. Βρέθηκαν σημαντικές διαφορές για τα δείγματα που εμβαπτίστηκαν in vitro σε καφέ, τσάι και κόκκινο κρασί. Συμπερασματικά, οι νάρθηκες Vivera® και Essix® C+ παρουσίασαν παρόμοιες μεταβολές χρώματος μετά από στοματική χρήση τριμήνου. Οι νάρθηκες Vivera® εμφάνισαν ορατές μεταβολές που προκλήθηκαν από καφέ, τσάι και κόκκινο κρασί. Όλες οι διαφορές που παρατηρήθηκαν θεωρήθηκαν κλινικά αποδεκτές.
description: Aims of the study were to investigate the in vitro effect of different staining solutions on the color stability of Vivera® retainers and to assess in vivo the color alterations of two thermoplastic retainers, Vivera® and Essix® C+. For the in vitro study, 30 flat specimens fabricated using the polyurethane-based Vivera® material (Align Technology Inc., CA, USA) were assigned into five groups (A, B, C, D and E) and immersed at 37°C in solutions of distilled water (control), coffee, tea, red wine, and Coca- Cola®, respectively. The CIE LAB parameters of each specimen were measured with a UV2401PC UV-VIS Recording Spectrophotometer before immersion (T0) and after 12 hours (T1), three days (T2) and seven days (T3) of exposure. ΔΕ differences were calculated. For the in vivo study, 30 patients were randomly allocated into two groups after orthodontic treatment. Group 1 (n=15) received Vivera® retainers and Group 2 (n=15) received Essix® C+ retainers (Raintree Essix, New Orleans, LA, USA). For each patient, control retainers were also fabricated. The CIE LAB parameters of each patient’s upper central incisors were measured with a SpectroShade™ Micro spectrophotometer immediately after retainer insertion in the mouth (T0) and after 15 days (T1), 1 month (T2) and 3 months (T3) of use. The measurements were also performed both with and without the control retainer on (tooth-only). ΔΕ differences were calculated. For the in vitro study, significant differences were observed concerning (i) L* between T3 and T0, T1 and T2 for Group B; (ii) a* between T0 and T1, T2 and T3 for Groups B, C, D and E, as well as between T1 and T2 for Group C; and (iii) b* between T0 and T1, T2 and T3 for Group B and between T0 and T2 and T3 for Group C. The differences between ΔΕ(T1-T0), ΔΕ(T2-T0) and ΔΕ(T3-T0) were statistically significant for Groups B and C, as well as the difference between ΔΕ(T1-T0) and ΔΕ(T2-T0) for Group D. For the in vivo study, no significant differences in ΔΕ changes were observed between Vivera® and Essix® C+ groups. ΔΕ(T3-T0) changes for used retainers were higher than those of control retainers and teeth-only. For used retainers, color changes between T3 and T0 were higher than those between T1 and T0 and between T2 and T0. The in vitro study indicates that the color of Vivera® retainers exhibited visible changes induced by several staining solutions, especially coffee, tea and, to a lesser extent, red wine. The in vivo study indicates that the used retainers exhibited greater color changes than control retainers or teeth. These changes became more pronounced with the duration of use. Vivera® and Essix® C+ retainers exhibited similar color stability over a 3 month period of use.