Ahmet ÖZLÜ, Gülşah TONGA, Hüseyin HATIRLI
European Oral Research - 2026;60(1):320-328
Purpose: This study aimed to evaluate and compare the immediate and aged microtensile bond strengths (µTBS) and pre-aging adhesive layer thicknesses of G2-Bond Universal, a novel two-bottle universal adhesive, with those of the gold-standard two-step self-etch adhesive (Clearfil SE Bond) and one-step universal adhesive (G-Premio Bond). Materials and Methods: Thirty extracted human molars were randomly assigned to three adhesive systems (n=10 teeth per group). After standardized dentin surface preparation, adhesives were applied according to manufacturers' protocols, followed by incremental composite build-up. Specimens were sectioned to obtain rectangular prism-shaped sticks (1 mm2 cross-sectional area), which were allocated to immediate and 6-month water aging subgroups (n=90 each). µTBS was measured using a universal testing machine. Adhesive layer thickness was assessed on 90 pre-aging sticks via scanning electron microscopy, with measurements performed using ImageJ software. Data were analyzed using two-way ANOVA for µTBS and one-way ANOVA for adhesive thickness, followed by Tukey's HSD. Results: Aging showed no statistically significant effect on µTBS (p > 0.05). Clearfil SE Bond exhibited the highest µTBS values, significantly outperforming G-Premio Bond (p < 0.05), while no statistically significant difference was observed compared with G2-Bond Universal (p > 0.05). G2-Bond demonstrated the thickest adhesive layer. Conclusion: The thicker adhesive layer of G2-Bond may enhance its mechanical resilience and clinical durability under functional stresses.
