Background: /purpose: The quality of the hybrid layer is of great importance for dentin bonding. The purpose of this study was to develop a novel copper-based pretreatment and investigate the effect of the pretreatment combined with universal adhesives on the dentin bond strength.
Materials and methods: Etch-and-rinse adhesive Single Bond 2 (SB2) and two universal adhesives Prime Bond Universal (PBU) and Single Bond Universal (SBU) were selected. The dentin surfaces were pretreated with CuSO4 solution and K2HPO4 solution in turn (Cu-P pretreatment), and the adhesive was applied following the manufacturer's instructions. There were four groups of Cu-P pretreatment: HH-Cu (1.5 mol/L CuSO4 + 1.0 mol/L K2HPO4); H-Cu (0.15 mol/L CuSO4 + 0.1 mol/L K2HPO4); L-Cu (0.015 mol/L CuSO4 + 0.01 mol/L K2HPO4); and LL-Cu (0.0015 mol/L CuSO4 + 0.001 mol/L K2HPO4). The microtensile bond strength (μ-TBS) and fracture mode were determined. The dentin surface after pretreatment and the antimicrobial properties of the pretreatment agent were also evaluated.
Results: The minimum inhibitory concentration and minimum bactericidal concentration of Cu-P pretreatment were 0.012 mol/L CuSO4 + 0.008 mol/L K2HPO4. Combined with SB2, the H-Cu and L-Cu groups showed a higher μ-TBS (P < 0.01), while the HH-Cu group showed a lower μ-TBS (P < 0.001), and the LL-Cu group showed a similar μ-TBS with the control group without Cu-P pretreatment. Combined with universal adhesives PBU and SBU, the H-Cu and L-Cu groups also showed significantly increased μ-TBS (P < 0.01).
Conclusion: The copper-based pretreatment in combination with universal adhesives improved the dentin microtensile bond strength.
Keywords: Dentin bonding; Microtensile bond strength; Pretreatment agent; Universal adhesives.
© 2022 Association for Dental Sciences of the Republic of China. Publishing services by Elsevier B.V.