Accelerated Aging Effects on Color, Translucency and Gloss of Composites

Objective: To evaluate the effect of accelerated aging on color, translucency parameter (TP) and gloss of four resin composites. Methods: Specimens (n=5) of four resin composites [Filtek Supreme Plus (FS, 3M ESPE, St. Paul, MN), Clearfil Majesty (CM, Kuraray America, New York, NY), Premise (PR, Kerr Corporation, Orange, CA), and Tetric EvoCeram (TE, Ivoclar Vivadent, Amherst, NY)] were polymerized against a Mylar strip, finished with 400-grit SIC paper, and polished with PoGo polisher(Dentsply Caulk, Milford, DE) for 40seconds. Color, TP and gloss were evaluated before and after exposure to 150 kJ/m² in an accelerated aging chamber. Color and TP were measured with a spectrophotometer, and gloss was measured using small-area glossmeter. Data were analyzed by analysis of variance and Fisher's PLSD intervals (p=0.05). Results: Means (s.d.) for color differences (DE^*), TP and gloss (GU) before aging (BA) and after aging (AA) are listed.

Composite	DE*	TP		Gloss (GU)
	BA-AA	BA	AA	BA	AA
FS	1.7(0.3)a	5.3(0.8)b	4.9(0.8)b	85.0(1.8)e	88.9(3.0)
CM	1.8(0.6)a	5.6(1.0)b	5.2(0.9)b	77.2(3.9)d	79.0(1.5)d
PR	2.9(0.9)	5.4(0.4)b	5.0(0.5)b	77.7(5.2)d	79.3(5.4)d
TE	1.6(1.1)a	7.5(0.4)c	7.0(0.8)c	81.6(3.7)ef	81.8(5.0)f

Fisher's PLSD interval for comparisons among products for color difference was 1.0. Fisher's PLSD intervals for condition and among products for TP were 0.5 and 0.7, respectively. Corresponding values for gloss were 2.5 GU and 3.6 GU. Conclusion: All materials exhibited aging-dependent color difference of DE*<3.0. Premise showed a statistically higher degree of color change as compared to other materials. There were no statistically significance differences for TP between before and after aging or among products except for Tetric EvoCeram. There was a statistical difference among composites for gloss. However, only Filtek showed a significant aging-dependent difference in gloss. All composites retained high gloss values after aging. Funded in part by Kuraray America.