Evaluation of natural tooth color space of the Indian population and its comparison to manufacturer's shade systems

Abstract

Purpose: This study evaluated the natural tooth color space of the Indian population and compared it with the manufacturer's shade systems. Materials and Methods: Maxillary central incisors of individuals aged 18–30 years and shade tabs of Vita Lumin vaccum (VL), Vitapan 3D master (V3D), and Shofu's Vintage Halo (SVH) shade guide were digitally photographed under standardized conditions. L*a*b* values from middle part of tooth and shade tab were attained using Adobe Photoshop 7.0 software. Comparative evaluation between the natural teeth and shade tabs was done, and color differences were noted and analyzed using appropriate software. Results: The L*a*b* values of the Indian population displayed a broader range than the shade guides. The mean Δ E* for VL shade guide was 7.22, 7.99 for SVH, and 8.39 for V3D, which was statistically significant. Color space of the Indian population on displayed an elongated cone with an irregular base. The plots of all the three shade guides were narrower and shorter and deficient in the blue–green region as compared to the population. Conclusions: Within the limitations of this study, the mean color difference between the Indian population and the three shade guides was above the acceptability thresholds (ΔE* = 2.7–6.8). VL, V3D, and SVH shade guides were deficient in their coverage and therefore can be considered inconsistent.

Keywords

• CIE L*a*b*
• color difference
• digital photography
• shade guide
• tooth color space