Table 1:

The color parameter values in the four groups of white substrate (W), nickel-chromium alloy (NCA), non-precious gold alloy (NPGA) and zirconia ceramic (ZRC)

Substrate group	Color parameter	Mean	Standard deviation	Minimum	Maximum	%95 confidence interval
W	L *	88.35	1.46	85.40	90.50	(87.31, 89.39)
	a *	−0.40	0.42	−1.10	0.30	(−0.70, −0.10)
	b *	3.38	0.36	2.90	4.10	(3.12, 3.64)
NCA	L *	78.24	1.31	76.10	80.00	(77.31, 79.17)
	a *	0.04	0.52	−0.40	1.40	(−0.33, 0.41)
	b *	1.92	1.01	0.70	4.00	(1.20, 2.64)
	ΔE	10.26	2.43	6.22	14.65	(8.52, 12.00)
NPGA	L *	78.98	1.26	76.50	80.80	(78.08, 79.88)
	a *	0.60	0.42	0.20	1.70	(0.30, 0.90)
	b *	3.86	0.49	3.30	4.90	(3.51, 4.21)
	ΔE	9.45	1.74	5.83	12.29	(8.21, 10.70)
ZRC	L *	82.16	1.16	80.30	83.90	(81.33, 82.99)
	a *	1.52	0.38	1.00	2.30	(1.25, 1.79)
	b*	4.88	0.57	4.30	6.20	(4.48, 5.28)
	ΔE	6.70	1.91	2.66	9.17	(5.33, 8.07)