Gülgezen Aydın H, et al. J Adv Prosthodont. 2026 Feb;18(1):16-24. https://doi.org/10.4047/jap.2026.18.1.16

Objective: To compare the CIE L*, a*, and b* color parameters of various 3D-printed and direct composite resins, all labeled with the A2 shade, and to evaluate whether their color differences (ΔE₀₀) relative to the VitaPan A2 reference standard remain within clinically acceptable thresholds. Materials and Methods: Three direct resin composites and two ceramic-filled 3D-printed crown resins were evaluated. For each material, six disc-shaped specimens (10 mm × 2 mm) were fabricated, all corresponding to the Vita A2 shade. Color measurements were obtained using a spectrophotometer within the CIE L*a*b* color space. Color differences relative to the Vita Pan A2 standard were calculated employing the CIEDE2000 formula (ΔE₀₀). Statistical analyses were conducted using one-way ANOVA, followed by Bonferroni and Games-Howell post hoc tests (p < 0.05). Results: Significant differences were observed among the materials with respect to L*, a*, b*, and ΔE₀₀ values (p < 0.001). Crowntec exhibited the highest L* value, whereas Charisma Smart demonstrated the highest a* value. Charisma Smart, Crowntec, and Permanent Crown presented higher b* values compared to Estelite Sigma Quick and Filtek Z250. Although Filtek Z250 and Estelite Sigma Quick displayed comparable ΔE₀₀ values, only Filtek Z250 remained below the clinical acceptability threshold (ΔE₀₀ < 1.8), indicating an acceptable color match with the VitaPan A2 shade. Conclusion: Resin-based materials labeled as A2 showed significant differences in L*, a*, b*, and ΔE₀₀ values, indicating that the A2 shade label does not ensure a clinically acceptable color match with the VitaPan A2 shade, as only Filtek Z250 exhibited ΔE₀₀ values below the threshold for clinical acceptability.

Akademisyen Yayınevi yöneticileri, yaklaşık 30 yıllık yayın tecrübesini, kendi tüzel kişiliklerine aktararak uzun zamandan beri, ticarî faaliyetlerini sürdürmektedir. Anılan süre içinde, başta sağlık ve sosyal bilimler, kültürel ve sanatsal konular dahil 2000’i aşkın yayımlamanın gururu içindedir. Uluslararası yayınevi olmanın alt yapısını tamamlayan Akademisyen, Türkçe ve yabancı dillerde yayın yapmanın yanında, küresel bir marka yaratmanın peşindedir. Bilimsel ve düşünsel çalışmaların kalıcı belgeleri sayılan kitaplar, bilgi kayıt ortamı olarak yüzlerce yılın tanıklarıdır. Matbaanın icadıyla varoluşunu sağlam temellere oturtan kitabın geleceği, her ne kadar yeni buluşların yörüngesine taşınmış olsa da, daha uzun süre hayatımızda yer edineceği muhakkaktır.

This in vitro study aimed to evaluate different fabrication techniques for anterior cobalt-chromium (Co-Cr) three-unit fixed dental prostheses (FDPs) and t

This study assessed the effects of material system, build orientation, thickness, and immersion time on optical properties. A total of 224 discs (n = 7 per subgroup) were fabricated from Permanent Crown Resin (system F) and Saremco Print CROWNTEC (system S) at 0° and 90° orientations and 1- and 2-mm thicknesses. Specimens were immersed in distilled water, coffee, tea, or red wine and measured at baseline and days 1, 7, and 30. Baseline CIELAB coordinates and changes in color (ΔE₀₀) and relative translucency parameter (ΔRTP₀₀) were analyzed by three-way and medium-specific four-factor mixed analyses of variance, respectively (α = 0.05). Material system dominated baseline variation (η_p² = 0.70–0.94); system S was lighter with lower a^* and b^* values. Time affected ΔE₀₀ in all media and ΔRTP₀₀ in staining media (p < 0.001). All between-specimen factors affected both outcomes in staining media, with medium-specific interactions. Descriptively, red wine produced the greatest changes; all red-wine groups exceeded the color acceptability threshold at day 30. System F at 90° and 1 mm showed the largest changes (ΔE₀₀ = 41.46 ± 9.48; ΔRTP₀₀ = 5.57 ± 0.85). No 2-mm group exceeded the translucency acceptability threshold. Optical behavior depended on configuration and exposure. System S showed greater color stability, mainly at 0°, whereas 90° orientation and reduced thickness generally increased optical change. Material, printing and post-polymerization effects could not be separated.