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The electrodissolution behavior of Cu and Cu‐rich Cu‐Zn alloys in 1M normalHCl containing benzotriazole (BTA) was studied using rotating ring‐disk electrodes. Cu(I) was the main product of Cu‐Zn alloy dissolution with Cu(II) detected only at higher potentials. Electrodissolution of the Cu component was similar to that of copper with an apparent Tafel slope of 60 mV/dec. Cu component dissolution rates exhibited strong mass‐transfer effects in the entire potential range studied. A normalCuCl film formed on the alloy surfaces in the current peak region. In the limiting current region the rates of Cu(I) dissolution from both alloys and copper were esentially equivalent and indicate CuCl2− as the principal diffusing species. Significant selective electrodissolution of Zn was observed in the apparent Tafel region. The formation of a duplex film was indicated in the presence of BTA with a nonporous Cu(I) BTA inner layer and a porous normalCuCl outer layer.

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Purpose To evaluate the push-out bond strength (PBS) and failure mode of single adjustable (SAP) and customized (CP) posts cemented to root canal dentin using conventional (RelyX Ultimate) or self-adhesive (RelyX U200) dual-cure resin cements. Methods Herein, 40 bovine mandibular incisors were divided into four groups (n = 10): SAP cemented with RelyX Ultimate (SAP-UT), SAP cemented with RelyX U200 (SAP-U2), CP cemented with RelyX Ultimate (CP-UT), and CP cemented with RelyX U200 (CP-U2). PBS and failure modes were analyzed. Three-way repeated measures ANOVA test followed by Tukey’s test and Fisher–Freeman–Halton exact test were used for data analysis (α = 5%). Results The PBS values for SAP (p < .05) were higher than those for CP and were not influenced by the root third and resin cement (p > .05). When conventional resin cement was used, the SAP showed significant differences compared to CP (p < .05). When cemented with RelyX Ultimate, a higher prevalence of mixed and adhesive failures for SAP and CP, respectively, was observed (p < .05). For the self-adhesive resin cement, the failures were mostly adhesive (p < .05). Conclusion SAP showed better performance than CP. The root third and resin cements did not influence the PBS. The most prevalent failures were adhesive and mixed.

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