Changes in color and color parameters of dental resin composites after polymerization

✍ Scribed by Il-Jang Kim; Yong-Keun Lee

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 160 KB
• Volume: 80B
• Category: Article
• ISSN: 1552-4973
• DOI: 10.1002/jbm.b.30628

✦ Synopsis

Abstract

Objectives.

The objectives were to measure the color change of varied shades of dental resin composites after polymerization, and to determine the correlation among the polymerization color change and the changes in color parameters after polymerization.

Methods.

Eight light‐curing resin composites, a total of 41 shades, were studied. Color of specimens (1 mm in thickness) was measured on a reflection spectrophotometer before and after polymerization over a white background. Changes in color (Δ__E__*~ab~), and color parameters (Δ__L__*, Δ__C__*~ab~, Δ__a__*, and Δ__b__*: value after polymerization – value before polymerization) were calculated.

Results.

The range of changes in each shade of resin composites was 1.1–7.9 for color (Δ__E__*~ab~), −7.5 to 2.3 for Δ__L__*, −6.8 to 3.1 for Δ__C__*~ab~, −0.9 to 1.2 for Δ__a__*, and −6.8 to 3.1 for Δ__b__*. Δ__E__*~ab~, Δ__L__*, Δ__C__*~ab~, Δ__a__*, and Δ__b__* were influenced by the brand and shade of resin composites, and there was a significant interaction between two independent variables (p < 0.05). On the basis of the multiple regression analysis, in which Δ__E__*~ab~ after polymerization was set as a dependent variable and Δ__L__*, Δ__C__*~ab~, Δ__a__* and Δ__b__* as independent variables, multiple correlation coefficient (r) was 0.842 and the included predictors were Δ__L__* [standardized partial correlation coefficient (β) = −0.760] and Δ__C__*~ab~ (β = −0.715). This result indicated that the polymerization changes in color and color parameters were varied by the brand and shade of resin composites, and the polymerization color change was caused by the changes in lightness and chroma with the similar power of influence. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2007