Effect of Laser Etching on Glass Fiber Posts Cemented with Different Adhesive Systems.

Background: Glass fiber-reinforced posts have been preferred frequently because of some physical properties similar to the dentin, chemically bonding to dentin, biocompatibility, and esthetics.

Objective: This study aimed to evaluate the microleakage and bond strength of glass fiber posts cemented with various adhesive systems on laser-etched root canal walls.

Methods: Roots of 120 human mandibular premolars were divided into two groups for push-out bond strength test and the microleakage test (n = 60). Erbium-doped yttrium-aluminum-garnet (Er:YAG) laser etching of the root canal walls was carried out on half of the specimens in both test groups. The laser-treated and laser-nontreated groups were divided again into three subgroups (n = 10). Glass fiber posts (everStick Post) were luted using three different resin cements: total-etch (Variolink N), self-etch (Panavia F 2.0), and self-adhesive (Rely X Unicem). Three dentin discs were obtained from each root, and the bond strength of the glass fiber posts was measured by push-out tests. The dye penetration method was used to investigate coronal microleakage. In addition, surface treatments and the bonding interfaces were observed using scanning electron microscope.

Results: The highest bond strengths were observed for the total-etch and self-adhesive resin cement groups with laser etching (p < 0.05), and the lowest bond strength was obtained for the self-etch resin cement group (p < 0.05). There were no statistically significant differences in terms of microleakage (p > 0.05), except for the self-adhesive resin cement group (p < 0.05).

Conclusions: Er:YAG laser etching enhances the bonding strength of glass fiber posts. In addition, laser etching can reduce microleakage of self-adhesive resin cement.