Table 1.
Means and standard deviation of µSBS for various primers under different air-drying pressures and storage conditions (n = 12).
Figure 1.
Scanning electron microscopy images of representative failure modes in the CCP and ZPP subgroups.
(a, b) low and high magnification images of a mixed failure mode in the CCP-0.3 subgroup after thermocycling, with a large percentage of cohesive failure at the bonding interface and small area of primer remnant on the zirconia surface; (c, d) low and high magnification images of a mixed failure mode in the ZPP-0.1 subgroup without thermocycling, with a small percentage of cohesive failure mode; (e, f) low and high magnification images of complete adhesive failure in CCP-0.1 subgroup after thermocycling, with primer residues on the zirconia surface. (a, c, e) 50× magnification; (b, d, f) 5,000× magnification. A: adhesive failure from zirconia surface; C: cohesive failure in SA Luting resin cement.
Figure 2.
Failure modes analysis and primer film thickness result.
(a) Failure modes for the micro-shear bonding test after 3 days of water storage or 5,000 thermocycles. (b) Variation in primer film thickness as a function of air-drying pressure. Data presented are means and standard deviations (n = 6). For CCP subgroups, the same upper case letters represent absence of statistically significant difference (p>0.05). For ZPP subgroups, the same lower case letters represent absence of s statistically significant difference (p>0.05). Asterisks indicate significant differences between the two ceramic primers (p<0.05). (c) Correlations between primer film thickness and air-drying pressure for the CPP and ZPP ceramic primers.
Figure 3.
Surface roughness of specimens in subgroups.
(a–h) 3D surface images (350 µm×350 µm) of specimens obtained from optical profilometry in subgroups: (a) CCP-0.1 MPa; (b) CCP-0.2 MPa; (c) CCP-0.3 MPa; (d) CCP-0.4 MPa; (e) ZPP-0.1 MPa; (f) ZPP-0.2 MPa; (g) ZPP-0.3 MPa; (h) ZPP-0.4 MPa; (i) NP. (air blasted zirconia without primer application) (j) Mean roughness (Sa) of experimental subgroups and control NP in µm. Data are presented as means and standard deviations (n = 6). For CCP subgroups, the same upper case letters represent absence of statistically significant difference (p>0.05). For ZPP subgroups, the same lower case letters represent absence of s statistically significant difference (p>0.05). Asterisks indicate significant differences between the two ceramic primers (p<0.05). (k) Correlations between surface roughness and air-drying pressure in the CPP and ZPP ceramic primers.
Figure 4.
Representative environmental scanning electron microscopy of primed, air-blasted zirconia surfaces in subgroups.
(a) CCP-0.1 MPa; (b) CCP-0.2 MPa; (c) CCP-0.3 MPa; (d) CCP-0.4 MPa; (e) ZPP-0.1 MPa; (f) ZPP-0.2 MPa; (g) ZPP-0.3 MPa; (h) ZPP-0.4 MPa.