Influence of Cement Type and Relining Procedure on Push-Out Bond Strength of Fiber Posts after Cyclic Loading

The aim of this study was to evaluate the influence of cement type and relining procedure on push-out bond strength of fiber posts (FPs) after cyclic loading.

Forty bovine incisor roots were divided into four groups: group 1, FP luting with RelyX Unicem; group 2, FP relined with resin composite (FPC) luting with RelyX Unicem; group 3, FP luting with RelyX ARC; group 4, FPC luting with RelyX ARC. Afterwards, half the specimens were exposed to 250,000 cycles in a controlled chewing simulator. With the other half of the specimens in each group, the push-out test was performed 24 hours after FP luting (immediate groups). All roots were sectioned transversely, producing 1-mm-thick slices, and the push-out test was performed. Statistical analysis was performed using ANOVA and the Tukey test for post hoc comparisons (α = 0.05).

FPC had higher bond strengths than FP (p < 0.05). RelyX Unicem showed higher bond strength than RelyX ARC (p < 0.05). Cyclic loading did not significantly affect the bond strength value (p > 0.05).

The relining procedure and the cement type are important factors for the bond strength of FPs to root dentin.