Table 4.

Mean values of color change of different filling materials after exposure to tea

Time-line	Micro-hybrid			Nano-hybrid			Glass-ionomer
	∆L	∆a	∆b	∆L	∆a	∆b	∆L	∆a	∆b
Day 7	− 7.28 ± 1.09	8.9 ± 2.68	6.28 ± 3.76	− 6.34 ± 1.02	− 0.76 ± 0.56	5.84 ± 2.82	− 6.84 ± 1.23	1.92 ± 1.92	− 0.18 ± 2.15
Day 30	− 12.16 ± 1.74	11.4 ± 3.82	9.94 ± 4.0	− 9.2 ± 1.2	5.0 ± 3.75	10.78 ± 3.55	− 10.96 ± 4.22	4.48 ± 1.65	− 0.5 ± 1.3