ANALYSIS OF CIELAB VALUES AND COLOR DIFFERENCES OF TWO DIFFERENT SHADE GUIDES USED IN DENTISTRY

Abstract

Aim: This study aims to compare the color parameters of two different dental shade guides from local and international manufacturers (Eray Deluxe and Vita Classical). Method: A total of 320 shade samples from 10 shade guides of each brand (n=10) were evaluated. Color measurements were performed under standard lighting conditions using a spectrophotometer. Each shade sample was measured six times, and the L*, a*, and b* values were recorded in the CIELAB color space. Color differences were calculated using the CIEDE2000 (ΔE₀₀) formula. Statistical analyses were conducted using the Kolmogorov-Smirnov test, independent samples t-test, and Mann-Whitney U test (α=0.05). Results: The ΔE₀₀ values of the Eray Deluxe shade guide were significantly higher in all color groups compared to the Vita Classical guide (p < 0.001). The largest difference was observed in the D color group, while the smallest difference was found in the A color tones. The L* values of the Eray shade guide were higher in the D color group, while the a* values were generally lower (p < 0.05). On the b* axis, the Eray shade guide exhibited more yellowish tones. Significant ΔE₀₀ differences were detected between the two shade guides in the most commonly selected shades (A1, A2, A3, B1, and B2). Conclusions: Neither shade guide perfectly matched the target colors, but the Vita Classical guide showed lower ΔE₀₀ values, indicating a closer match to the target shades. In clinical practice, differences between shade guides should be considered.

Keywords

• Color Mismatch
• Dental Technician
• Optical Properties
• Pigment Variation
• Spectrophotometry

Diş Hekimliğinde Kullanılan İki Farklı Renk Skalasının CIELAB Değerleri ve Renk Farklılıklarının Analizi

Öz

Amaç: Bu çalışma, yerel ve uluslararası üreticilere ait iki farklı renk skalasının (Eray Deluxe ve Vita Classical) renk parametrelerini karşılaştırmaktır. Yöntem: Çalışmada, her iki markaya ait 10 adet renk skalası (n=10) kullanılarak toplam 320 renk örneği değerlendirildi. Renk ölçümleri, standart ışık koşulları altında bir spektrofotometre ile gerçekleştirildi. Her bir renk numunesinden altı ölçüm alındı ve CIELAB renk uzayında L*, a* ve b* değerleri kaydedildi. Renk farklılıkları, CIEDE2000 (ΔE₀₀) formülü kullanılarak hesaplandı. İstatistiksel analizler Kolmogorov-Smirnov testi, bağımsız örneklem t-testi ve Mann-Whitney U testi ile yapıldı (α=0,05). Bulgular: Eray Deluxe renk skalasının ΔE₀₀ değerleri, tüm renk gruplarında Vita Classical’a kıyasla anlamlı derecede daha yüksek bulundu (p < 0,001). En büyük fark D renk grubunda gözlenirken, en düşük fark A renk tonlarında saptandı. Eray Deluxe renk skalasının L* değerleri D renk grubunda daha yüksek, a* değerleri ise genel olarak daha düşük bulundu (p < 0,05). b* ekseninde Eray Deluxe renk skalasının daha sarı tonlara sahip olduğu belirlendi. Klinik olarak en sık kullanılan renk tonlarında (A1, A2, A3, B1 ve B2) her iki renk skalası arasında anlamlı ΔE₀₀ farkları tespit edildi. Sonuçlar: Her iki renk skalasının da hedef renklere tam uyumlu olmadığı, ancak Vita Classical’ın daha düşük ΔE₀₀ değerleriyle hedef renge daha yakın olduğu belirlendi. Klinik pratikte, renk seçiminde kullanılan skalalar arasındaki farklılıklar göz önünde bulundurulmalıdır.

Anahtar Kelimeler

• Diş Teknisyeni
• Optik Özellikler
• Pigment Varyasyonu
• Renk Uyumsuzluğu
• Spektrofotometri

Kaynakça

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