title: Influence of background color on the color changes of resin composites after accelerated aging.
abstract: OBJECTIVE
  To evaluate the changes in color and color coordinates after accelerated aging of resin composites depending on the background color.
  
  
  METHODS
  Color of seven resin composites (14 shades, 1 mm-thick) was measured in the reflectance mode over a zero calibration box, a white background, and a black background. After baseline color measurement, specimens were aged for total energy of 150 kJ/m2. Color change after aging was calculated over three backgrounds. Based on the data of A2 shade composites, the influence of the background color on the changes in color (deltaE*ab) and changes in three color coordinates (deltaL*, deltaa* and deltab*) after aging was analyzed by ANOVA (P < 0.01). Correlation among the color changes over three backgrounds was determined with a linear regression analysis.
  
  
  RESULTS
  Background color influenced deltaE*ab, deltaL*, deltaa* and deltab* values. There were significant correlations among the color changes over three backgrounds in the reflectance mode (r = 0.95-0.98).
authors: Department of Dental Biomaterials Science, Dental Research Institute, College of Dentistry, Seoul National University, Seoul, Korea. ykleedm@snu.ac.kr
authors: Yong-Keun
authors: YK
authors: Lee
authors: John M
authors: JM
authors: Powers
mesh_terms: D003116:Color; D003188:Composite Resins / Q000737:chemistry* / Q000528:radiation effects; D006801:Humans; D006813:Humidity; D008027:Light; D008422:Materials Testing; D055095:Optics and Photonics; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors
chemical_list: D003188:Composite Resins; C507124:Estelite sigma; C466112:Esthet-X; C474035:Filtek Supreme; C467914:TPH spectrum; C121818:Tetric ceram; C086113:palfique estelite