Shear Bond Strength of Colored and Sandblasted Zirconia to Ceramic Veneers Fabricated by the Pressing and Layering Techniques: An In Vitro Study

Table 2

Measures of central dispersion for SBS (MPa) of the study groups.

Groups	Mean ± SD	95% confidence interval
		Lower bound	Upper bound
CP^A+	13.76 ± 1.89	9.96	17.57
CL^a	23.65 ± 1.79	20.04	27.26
SP^B+	24.40 ± 1.79	20.79	28.01
SL^b	17.79 ± 1.79	14.18	21.40
AP^C+	20.40 ± 1.79	16.79	24.01
AL^c	22.74 ± 1.79	19.13	26.35

AP, control pressed; AL, control layered; CP, colored pressed; CL, colored layered; SP, sandblasted pressed; SL, sandblasted layered; SBS, shear bond strength; MPa, megapascals; SD, standard deviation. Different superscripted letters (uppercase and lowercase) indicate that the difference between each treatment subgroups (for different veneering technique) is significant as determined by independent t-test (). Also, + symbol indicates that the difference between each veneering subgroups (for different treatment) is significant as determined by independent t-test ().