title: Influence of background/surrounding area on accuracy of visual color matching.
abstract: BACKGROUND
  Visual shade selection is subjective and influenced by factors that might be operator-dependent or not. The objective was to evaluate influence of observer nonrelated factors (background/surrounding area, and light) and observer-related factors (gender and color competence) on shade-matching quality and to identify the most often mismatched shades in correlation with the background.
  
  
  METHODS
  Ten observers with average or superior color discrimination competence according to ISO TR 28642:2011 were asked to match 48 shade tabs of three VITA Classical shade guides, in a viewing booth under two light sources: D65 and D50. Gray, white, black, red, and light blue background/surrounding area simulated various clinical situations. The results were statistically analyzed using Kruskal-Wallis test and Mann-Whitney U test. Post hoc power analyses and sample size calculations were also conducted.
  
  
  RESULTS
  The matching scores ranged between 72.7 % (using blue background) and 85.9 % (using white and black backgrounds). There was a statistically significant difference between matching scores on the five backgrounds (χ (2)(4) = 12.67, p = 0.01). When neutral gray was used as reference, Mann-Whitney U value was statistically significant only for the blue background (U = 107.00, Z = -2.52, p = 0.01). The influence of gender and lighting condition was also assessed, no statistically significance being found, but in both cases, the effect size and the achieved power were small. However, color discrimination competence did influence the results (p < 0.01). Background influenced shade matching results for tabs A3, B3, B4, and D4.
  
  
  CONCLUSIONS
  Within the limitations of this study, it was concluded that 1. When it comes to the influence of the background/surround area on quality of color matching, no difference among achromatic backgrounds was recorded. Significantly worse results were recorded when the blue background was used. 2. Observers with superior color matching competence performed significantly better than the ones with average competence 3. The most frequently mismatched shade tabs were A3.5, B3, B4, and D4.
authors.affiliation: University Medicine and Pharmacy Iuliu Hatieganu, Cluj-Napoca, Romania. ddudea@umfcluj.ro.
authors.forename: Diana
authors.initials: D
authors.lastname: Dudea
authors.affiliation: University Medicine and Pharmacy Iuliu Hatieganu, Cluj-Napoca, Romania.
authors.forename: Cristina
authors.initials: C
authors.lastname: Gasparik
authors.affiliation: University Medicine and Pharmacy Iuliu Hatieganu, Cluj-Napoca, Romania.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Botos
authors.affiliation: University Medicine and Pharmacy Iuliu Hatieganu, Cluj-Napoca, Romania.
authors.forename: Florin
authors.initials: F
authors.lastname: Alb
authors.affiliation: University Medicine and Pharmacy Iuliu Hatieganu, Cluj-Napoca, Romania.
authors.forename: Ada
authors.initials: A
authors.lastname: Irimie
authors.affiliation: Houston Center for Biomaterials and Biomimetics, University of Texas School of Dentistry at Houston, Houston, USA.
authors.forename: Rade D
authors.initials: RD
authors.lastname: Paravina
mesh_terms: D002138:Calibration; D003116:Color; D003118:Color Perception / Q000502:physiology*; D017267:Dental Prosthesis Design; D005260:Female; D006801:Humans; D008027:Light; D008297:Male; D015588:Observer Variation; D017797:Prosthesis Coloring; D012737:Sex Factors
keywords: Background; Color matching; Shade guide