The Effect of Varying Dentin Chroma and Enamel Thickness on the Color of A2 Double-layered Resin Composite

E H Ismail; D V Dawson; Cmp Vidal; F N Skiff; K Brogden; R R Maia

doi:10.2341/21-138-L

The Effect of Varying Dentin Chroma and Enamel Thickness on the Color of A2 Double-layered Resin Composite

Oper Dent. 2022 Dec 15. doi: 10.2341/21-138-L. Online ahead of print.

Authors

E H Ismail¹, D V Dawson², Cmp Vidal³, F N Skiff⁴, K Brogden⁵, R R Maia⁶

Affiliations

¹ *Eman H Ismail, DDS, MS, PhD, assistant professor, Clinical Dental Science Department, Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia.
² Deborah V Dawson, BA, ScM, PhD, Department of Pediatric Dentistry and Iowa Institute for Oral Health Research, College of Dentistry; Department of Biostatistics, College of Public Health, The University of Iowa, Iowa City, IA, USA.
³ Cristina MP Vidal, DDS, MS, PhD, Department of Operative Dentistry, College of Dentistry, The University of Iowa, Iowa City, IA, USA.
⁴ Fredrick N Skiff, PhD, Department of Physics and Astronomy, The University of Iowa, Iowa City, IA, USA.
⁵ Kim Brogden, PhD, Iowa Institute of Oral Health Research, Department of Periodontics, The University of Iowa, Iowa City, IA, USA.
⁶ Rodrigo R Maia, DDS, MS, PhD, Department of Cariology, Restorative Sciences and Endodontics, School of Dentistry, University of Michigan, Ann Arbor, MI, USA.

PMID: 36520684
DOI: 10.2341/21-138-L

Abstract

Objectives: To evaluate chroma (C*) and overall color of double-layered (DL) resin composite (RC) restorations with various dentin shades and enamel thicknesses.

Methods: Enamel specimens were fabricated using custom-made molds to replicate VITA shade tabs with variant enamel thicknesses (0.5, 0.7, and 1.0 mm) (n=7) from two RC: Clearfil-Majesty (CM) shade (A2), and Vit-l-escence (VL), shade (pearl-neutral). Dentin specimens (shades A1, A2, and A3) were fabricated using custom molds corresponding to the enamel molds. Each enamel specimen was paired with three different dentin specimens. L*a*b* parameters were measured with VITA Easyshade-V. Color difference between DL specimens and the A2 VITA shade tab were calculated with the CIEDE2000 formula. Relationships among enamel thickness, ΔE00, C* of dentin layer, C* of DL, and change in chroma were assessed by Spearman rank correlations. ΔE00 was compared among groups using one-way analysis of variance with Tukey post-hoc adjustment for all possible pairwise group comparisons (experiment-wise α=0.05).

Results: There was no statistical difference among C* of DL specimens (p=0.65, 0.53) for CM and VL, respectively. Combinations of enamel thickness/ dentin shade had a significant difference in ΔE00 (p>0.05). No significant correlation was observed among enamel thickness and C* of dentin, and C* of the DL (p>0.05). Significant correlations were observed between ΔE00 of the VL DL and C* DL (r=-0.8, p<0.001); and ΔE00 of CM DL and enamel thickness (r=0.5, p<0.001).

Conclusions: Enamel thickness did not affect C* of the dentin layer. Unlike VL RC, variations in dentin shades with CM produced a closer match to the A2 shade tab. Enamel is recommended to be 0.7 mm or less.