Table 5.

Changes in yellowness of the restorative materials and the ceramic across 5 years.

Time
Material	b*(0 day)	b*(1 year)	b*(2 years)	b*(3 years)	b*(4 years)	b*(5 years)
Ceramic	12.72 ± 1.05aA	12.97 ± 1.04abA	13.39 ± 1.07cA	13.25 ± 1.21bcA	14.86 ± 1.27dA	14.84 ± 2.47dA
A1E	12.58 ± 1.56aA	12.5 ± 2.13bB	12.9 ± 2.22abA	12.76 ± 2.17bB	14.38 ± 2.33bB	14.34 ± 3.19bB
A2E	15.66 ± 1.16aB	11.66 ± 0.47bA	11.74 ± 0.3abA	11.73 ± 0.66bA	12.65 ± 0.44bA	12.25 ± 0.47bA
A3E	18.46 ± 1.74aB	15.38 ± 0.52cB	16.18 ± 0.94abcA	16.10 ± 1.5bcB	17.64 ± 2.25aB	17.78 ± 2.46abA
A1B	19.30 ± 3.42aB	15.70 ± 1.49bB	17.05 ± 1.45abA	16.86 ± 1.16bB	21.01 ± 1.71aB	20.64 ± 2.38aB
A2B	21.19 ± 2.59aB	17.44 ± 0.82bB	18.06 ± 0.8abA	17.36 ± 0.67bB	20.73 ± 2.92aB	20.36 ± 3.02aB
A3B	25.74 ± 3.24aB	20.11 ± 1.07cB	21.34 ± 0.75abcdA	19.59 ± 1.36bcB	22.78 ± 1.22 dB	23.09 ± 1.3adB
A1D	30.28 ± 2.3aB	24.74 ± 1.82cB	24.96 ± 2.03acdeA	23.33 ± 1.58bdB	26.49 ± 1.65eB	25.84 ± 1.46ceB
A2D	35.53 ± 1.94aB	31.94 ± 1.39cB	32.03 ± 1.20bcB	28.94 ± 1.52 dB	32.54 ± 1.13cB	32.04 ± 0.81cB
A3D	36.28 ± 5.04aB	31.08 ± 2.31cB	31.55 ± 1.29abcdA	28.24 ± 4.4 dB	33.56 ± 0.9bB	32.43 ± 1.83bcB
A1F	14.81 ± 2.17aceA	13.44 ± 1.42cA	13.24 ± 1.87acdA	13.65 ± 2.22acA	17.95 ± 1.4bdB	17.31 ± 1.54edA
A2F	17.21 ± 2.18aB	18.09 ± 3.49aB	18.53 ± 3.73abA	17.83 ± 4.73aB	21.93 ± 2.15bB	19.85 ± 2.41aB
A3F	24.21 ± 1.91aB	22.13 ± 1.08cB	23.26 ± 1.27abcdA	21.10 ± 1.70bcB	26.75 ± 1.36 dB	25.39 ± 1.50adB
A1BF	11.36 ± 0.81aA	9.33 ± 0.91bB	9.68 ± 1.12abA	9.09 ± 1.05bB	10.56 ± 1.52abB	10.23 ± 1.47abB
A2BF	13.09 ± 1.05aA	10.59 ± 0.3bB	10.94 ± 0.6abA	10.46 ± 0.85bB	12.45 ± 0.99aB	11.81 ± 1.79abA
A3BF	16.58 ± 0.79aB	14.35 ± 2.18bA	14.96 ± 2.2abA	14.13 ± 2.26bA	15.55 ± 3.01abA	15.78 ± 3.1abA
GI	43.69 ± 2.26aB	35.58 ± 2.48cB	33.11 ± 2.58abcdA	28.51 ± 7.67 dB	32.74 ± 5.56bB	32.30 ± 6.47bB

Lower case letters indicate significant difference within the row (p < 0.05).

Upper case letters indicate significant difference within the column (p < 0.05).