Purpose: To study the influence of a polyalkenoate copolymer (VCP) on the immediate (24 h) and 6-month dentin
bonding stability of VCP-based adhesives, using microtensile bond strength (μTBS), nanoleakage (NL), and ultra-morphological analyses (FE-SEM).
Materials and Methods: Eighty-four caries-free molars were randomly assigned to seven adhesives: Clearfil SE
Bond (CSE, Kuraray Noritake); Adper Single Bond Plus (SB, 3M ESPE); SB without VCP (SBnoVCP, 3M ESPE);
Scotchbond Universal Adhesive applied as a etch-and-rinse adhesive (SBU_ER); SBU without VCP applied as an
etch-and-rinse adhesive (SBUnoVCP_ER); SBU applied as a self-etch adhesive (SBU_SE, 3M ESPE); SBU without
VCP applied as a self-etch adhesive (SBUnoVCP_SE, 3M ESPE). Half of the beams were tested after 24 h, and the
other half was aged in water for 6 months prior to testing. For each tooth/evaluation time, two beams were randomly
selected for NL analysis. Statistical analyses of μTBS results were performed using two-way ANOVA, Tukey’s
post-hoc tests, and Student’s t-test for paired data (α= 0.05). Nanoleakage was statistically analyzed using the
Kruskal-Wallis and Mann-Whitney tests, with Wilcoxon’s test for paired data. For FE-SEM, four caries-free molars
were assigned to each of the seven groups. Dentin disks were restored and cross sectioned into halves. One half
was observed at 24 h, and the other at 6 months.
Results: The highest 6-month mean μTBS was obtained with SBU_SE/SBUnoVCP_SE and SBUnoVCP_ER.
SBUnoVCP_SE resulted in greater silver deposition at 6 months. FE-SEM observations showed that CSE and SBU_SE
specimens resulted in a submicron hybrid layer without signs of degradation at 6 months.
Conclusions: VCP may contribute to the long-term bonding stability of VCP-based adhesives.