title: Effect of Different In Vitro Aging Methods on Color Stability of a Dental Resin-Based Composite Using CIELAB and CIEDE2000 Color-Difference Formulas.
abstract: OBJECTIVE
  To evaluate the effect of different in vitro aging methods on color change (CC) of an experimental dental resin-based composite using CIELAB (ΔEab ) and CIEDE2000 (ΔE00 ) color-difference formulas.
  
  
  METHODS
  The CC was evaluated with a spectrophotometer (CM700d, Konica Minolta, Tokyo, Japan) according to the CIE chromatic space. Disk-shaped specimens (Φ = 5 × 1 mm thick) (N = 10) were submitted to different in vitro aging methods: 30 days of water aging (WA); 120 hours of ultraviolet light aging (UVA); or 300 hours of an accelerated artificial aging (AAA) method with cycles of 4 hours of UV-B light exposure and 4 hours of moisture condensation to induce CC. The temperature was standardized at 37°C for all aging methods. CC was evaluated with ΔEab and ΔE00 formulas. Differences in individual Lab coordinates were also calculated. Data for the individual color parameters were submitted to one-way analysis of variance and Tukey's test for multiple comparisons (α = 0.05).
  
  
  RESULTS
  All in vitro aging methods tested induced CC, in the following order: WA: ΔEab = 0.83 (0.1); ΔE00  = 1.15 (0.1) < AAA: ΔEab  = 5.64 (0.2); ΔE00  = 5.01 (0.1) < UVA: ΔEab  = 6.74 (0.2); ΔE00  = 6.03 (0.4). No changes in L* or a* coordinates were ≥1; the methods with UV aging showed a yellowing effect due a large positive change in b*.
  
  
  CONCLUSIONS
  All in vitro aging methods tested induced a CC, but to different extents. Changes in color followed similar trends, but with different absolute values when calculated with the CIELAB and the CIEDE2000 formulas.
  
  
  CONCLUSIONS
  Establishing the efficacy of different artificial aging methods and differences between color change using CIELAB and CIEDE2000 formulas are important to standardize color stability evaluations and facilitate the comparison of outcomes from different studies in the literature.
authors.affiliation: Department of Dental Materials, School of Dentistry, Oregon Health & Science University, 2730 SW Moody Avenue, Portland, OR, 97201, USA.|Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, 901 Limeira Avenue, Areiao, Piracicaba, SP, 13414-903, Brazil.
authors.forename: Dayane Carvalho Ramos Salles
authors.initials: DC
authors.lastname: de Oliveira
authors.affiliation: Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, 901 Limeira Avenue, Areiao, Piracicaba, SP, 13414-903, Brazil.
authors.forename: Ana Paula Almeida
authors.initials: AP
authors.lastname: Ayres
authors.affiliation: Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, 901 Limeira Avenue, Areiao, Piracicaba, SP, 13414-903, Brazil.
authors.forename: Mateus Garcia
authors.initials: MG
authors.lastname: Rocha
authors.affiliation: Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, 901 Limeira Avenue, Areiao, Piracicaba, SP, 13414-903, Brazil.
authors.forename: Marcelo
authors.initials: M
authors.lastname: Giannini
authors.affiliation: Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, 901 Limeira Avenue, Areiao, Piracicaba, SP, 13414-903, Brazil.
authors.forename: Regina Maria
authors.initials: RM
authors.lastname: Puppin Rontani
authors.affiliation: Department of Dental Materials, School of Dentistry, Oregon Health & Science University, 2730 SW Moody Avenue, Portland, OR, 97201, USA.
authors.forename: Jack L
authors.initials: JL
authors.lastname: Ferracane
authors.affiliation: Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, 901 Limeira Avenue, Areiao, Piracicaba, SP, 13414-903, Brazil.
authors.forename: Mario Alexandre Coelho
authors.initials: MA
authors.lastname: Sinhoreti
mesh_terms: D003116:Color; D003188:Composite Resins; D003764:Dental Materials; D066298:In Vitro Techniques; D014466:Ultraviolet Rays
chemical_list: D003188:Composite Resins; D003764:Dental Materials