Mrunal Vijay Deshmukh

ABSTRACT

Objective: To evaluate and compare the bond durability of a universal adhesive (Renew Universal, Prevest DenPro, India) and a gold-standard two-step self-etch adhesive (Clearfil SE, Kuraray, Japan) to enamel, dentin, zirconia, and nickel–chromium (Ni–Cr) alloy. Materials and Methods: Ninety-six specimens (n = 24 per substrate) of enamel, dentin, zirconia and Ni–Cr alloy were prepared according to ISO standards. Enamel and dentin were etched with phosphoric acid and zirconia and Ni–Cr were airborne-particle abraded. Renew Universal and Clearfil SE adhesive were applied and composite cylinders bonded. Specimens underwent thermocycling (5000 cycles, 5–55 °C). Shear bond strength was tested using a universal testing machine. Data were analyzed with two-way ANOVA and Tukey’s test (? = 0.05). Results: Enamel showed the highest bond strength in both groups (Renew Universal: 20.9 ± 2.3 MPa; Clearfil SE: 19.8 ± 2.1 MPa), while dentin showed the lowest (Renew Universal: 16.7 ± 2.0 MPa; Clearfil SE: 15.9 ± 1.8 MPa). Zirconia and Ni–Cr achieved intermediate values (Renew Universal: 18.2 ± 2.1 and 17.2 ± 1.9 MPa; Clearfil SE: 16.8 ± 2.0 and 15.7 ± 1.8 MPa, respectively). Thermocycling significantly reduced bond strength across all substrates (p < 0.05), but Renew Universal consistently outperformed Clearfil SE on zirconia and Ni–Cr (p < 0.05). Conclusion:Renew Universal demonstrated effective bonding to tooth structure and indirect restorative substrates. Its dual functional monomers, 10-MDP and 4-META, enhanced adhesion to zirconia and Ni–Cr. However, aging significantly compromised bond durability. Keywords: Universal adhesive, shear bond strength, enamel, dentin, zirconia, nickel–chromium, thermocycling.