title: [Color stability of ceromer of different thicknesses and resin adhesive materials of different types after accelerated aging].
abstract: OBJECTIVE
  This study aims to investigate the color stability of ceromer with different thicknesses and different types of resin adhesive materials after accelerated aging and provide references for clinical application and selections.
  
  
  METHODS
  Nine groups of experimental samples were used, and each group contained five samples. We made joint samples with ceromer having three different thicknesses (1.00, 0.75, 0.50 mm) combined with three different resin adhesive materials (RelyX Veneer, RelyX Unicem, Filtek Z350 Flow), respectively. All samples were placed into Xenon Lamp Aging Instrument to implement accelerated aging. Spectrophotometer was used to measure the lightness (L*), red green color value (a*), and blue yellow color value (b*) of all samples before and after accelerated aging. The change of lightness (ΔL), red green color value (Δa), blue yellow color value (Δb), and color variation (ΔE) were also calculated. We investigated the influence of ceromer veneer thicknesses and resin adhesive material types on color variation by two-factor analysis of variance.
  
  
  RESULTS
  The thickness and type factors showed significant influence on ΔE values, and exhibited interactions (P < 0.05). The ΔE values of all experimental groups were lower than 3.3. After the accelerated aging process, all L*, a*, and b* values of the experimental groups decreased and the ΔL values were lower than 2.0.
  
  
  CONCLUSIONS
  Ceromer veneer thickness and resin adhesive material types could affect the color stability of ceromer veneer and resin adhesive materials. The changes in lightness and color in ceromer veneer and resin adhesive materials are considered clinically acceptable after accelerated aging.
authors.forename: Wang
authors.initials: W
authors.lastname: Likai
authors.forename: Liu
authors.initials: L
authors.lastname: Yanan
authors.forename: Zheng
authors.initials: Z
authors.lastname: Yan
authors.forename: Li
authors.initials: L
authors.lastname: Pingping
mesh_terms: D002516:Ceramics; D003116:Color; D003188:Composite Resins; D003738:Dental Cements / Q000737:chemistry*; D008027:Light; D019279:Resin Cements
chemical_list: D003188:Composite Resins; D003738:Dental Cements; C483701:Rely X Unicem; D019279:Resin Cements; C111841:ceromer; C533204:filtek Z350