title: Comparison of color of resin composites of white and translucent shades with two shade guides.
abstract: OBJECTIVE
  The purpose of this study was to compare the color of resin composites of white, translucent, and conventional shades with shade guides, based on the analysis of the color distribution of shade guides. The influence of color measuring mode, specular component included (SCI) or excluded (SCE), was also determined.
  
  
  METHODS
  The labial portions of shade guide tabs (Vita and Chromascop) were polished flat with up to 2400-grit SiC paper. Color coordinates were measured according to CIE L*a*b* color scale on a reflection spectrophotometer with both the SCE and SCI modes. The color coordinates of white, translucent, and conventional shades of two brands of resin composites were measured and compared with those of the shade guides.
  
  
  RESULTS
  There was no logical order in the color distribution of the two shade guides. The color of white and translucent shades of resin composites was located on the low CIE a* and CIE b* value area. The CIE L*, a*, b* values of resin composite with the same color designations were different, depending on the brand of material. The color difference (deltaE*) of shade guides by the measuring mode (SCE vs. SCI) was between 3.2 and 6.5.
authors.affiliation: Department of Dental Biomaterials, College of Dentistry and Intellectual Biointerface Engineering Center, Seoul National University, Korea. ykleedm@snu.ac.kr
authors.forename: Y K
authors.initials: YK
authors.lastname: Lee
authors.forename: B S
authors.initials: BS
authors.lastname: Lim
authors.forename: C W
authors.initials: CW
authors.lastname: Kim
authors.forename: J M
authors.initials: JM
authors.lastname: Powers
mesh_terms: D003116:Color; D003188:Composite Resins / Q000737:chemistry*; D017267:Dental Prosthesis Design / Q000295:instrumentation*; D004867:Equipment Design; D006801:Humans; D008027:Light; D013053:Spectrophotometry; D013499:Surface Properties
chemical_list: D003188:Composite Resins