Comparison of Color Changes of Vacuum Formed Retainers Made from PET-G Material: An in-vitro Study

Yıl 2025, Cilt: 7 Sayı: 2, 163 - 168, 29.08.2025

Barış Can Telatar , Günseli Katırcı , Gül Yıldız Telatar

Öz

Aim: Polyethylene terephthalate glycol (PET-G) materials are frequently used in dental practice. Most vacuum formed retainers (VFRs) and trays for bleaching agents are made from PET-G materials. The aim of this in vitro study was to evaluate the color stability of different branded VFRs, made from PET-G material, in various beverages.
Materials and Methods: Two different PET-G materials, Atmos (American Orthodontics, Washington, USA) and Duran (Scheu Dental, Iserlohn, Germany) were tested after thermoforming over a metal casting model of 15 mm diameter and 6 mm height for color stability. Ten samples from each brand were immersed in four different beverages (water, tea, coffee, and coke), and a total of 80 samples were evaluated on the 7th and 14th days using a spectrophotometer. Color changes were evaluated based on the L*,a*,b* color system, according to Commission Internationale de l'Eclairage (CIE). One-way ANOVA was used for ∆E. Student’s t-test and Bonferroni tests were applied to compare the variables. The level of statistical significance was set at P < .05
Results: There were statistically significant differences between Atmos and Duran. (P < .001). Duran showed significant color changes with tea, coffee, and water (p< 0.05) while Atmos were more resistant to discoloration.
Conclusion: It was observed that different PET-G materials showed varying performance against discoloration. Duran was more prone to discoloration compared with Atmos. Tea had the greatest discoloration effect on all groups.
Keywords: PET-G, color stability, orthodontic retainers, in vitro

Anahtar Kelimeler

orthodontics , coffee , water , orthodontic retainers

PET-G Malzemesinden Üretilen Vakumla Şekillendirilmiş Tutucuların Renk Değişimlerinin Karşılaştırılması: Bir in-vitro Çalışma

Öz

Amaç: Polyethylene terephthalate glycol (PET-G) malzemeleri diş hekimliğinde sıklıkla kullanılmaktadır. Vakumla şekillendirilmiş tutucular (VFR) ve beyazlatma maddelerine yönelik plakların çoğu PET-G malzemelerinden yapılır. Bu in-vitro çalışmanın amacı, PET-G materyalinden yapılan farklı markalı VFR'lerin farklı içeceklerdeki renk stabilitesini değerlendirmektir.
Gereç ve Yöntemler: İki farklı PET-G malzemesi Atmos (American Orthodontics, Washington, ABD) ve Duran (Scheu Dental, Iserlohn, Almanya), 15 mm çapında ve 6 mm yüksekliğinde metal döküm modeli üzerinde ısıyla şekillendirme sonrasında renk stabilitesi açısından test edildi. Her markadan 10'ar numune dört farklı içecekte (su, çay, kahve ve kola) bekletilerek 7. ve 14. günlerde toplam 80 numune spektrofotometre kullanılarak değerlendirildi. Renk değişiklikleri, Commission Internationale de l'Eclairage'e (CIE) L*, a*, b* renk sistemine göre değerlendirildi. ∆E için tek yönlü ANOVA kullanıldı. Değişkenleri karşılaştırmak için Student t-testi ve Bonferroni testleri uygulandı. İstatistiksel anlamlılık düzeyi P < ,05 olarak belirlendi
Bulgular: Atmos ve Duran arasında istatistiksel olarak anlamlı farklar vardı (P < ,001). Duran çay, kahve ve su ile belirgin renk değişiklikleri gösterirken (P < ,05), Atmos ise renk solmasına karşı daha dirençliydi.
Sonuç: Farklı PET-G malzemelerinin renk solmasına karşı farklı performans gösterdiği gözlendi. Duran, Atmos' a kıyasla renk bozulmasına daha yatkın olarak bulundu. Çay, her grup için en fazla renk değişikliği etkisine sahipti.

Anahtar Kelimeler

ortodonti , kahve , su , ortodontik sabitleyici

Kaynakça

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