Shear bond strength of one-step self-etch adhesives: pH infl uence

Abstract

Background: The aim of this study was to compare the shear bond strength of four one-step
self-etch adhesives with different pH values to enamel and dentin.
Materials and Methods: In this in vitro study, 200 bovine permanent mandibular incisors were
used. Four one-step self-etch adhesives with different pH values were tested both on enamel and
on dentin: Adper™ Easy Bond Self-Etch Adhesive (pH = 0.8-1), Futurabond NR (pH=2), G-aenial
Bond (pH = 1.5), Clearfi l S3 Bond (pH = 2.7). After adhesive systems application, a nanohybrid
composite resin was inserted into the bonded surface. The specimens were placed in a universal
testing machine. The shear bond strength was performed at a cross-head speed of 1 mm/min until
the sample rupture. The shear bond strength values (MPa) of the different groups were compared
with analysis of variance after that Kolmogorov and Smirnov tests were applied to assess normality
of distributions. P < 0.05 was considered as signifi cant.
Results: In enamel shear bond strength, the highest shear bond strength values were reported
with Futurabond NR (P < 0.01); however, no signifi cant differences were found with Clearfi l S3 Bond.
The others adhesive systems showed lower shear bond strength values with signifi cant differences
between them (P < 0.05). When comparing the dentin shear bond strength, the lowest shear bond
strength values were reported with Clearfi l S3 Bond (P < 0.05), while there were no signifi cant
differences among the other three products (P > 0.05).
Conclusion: The pH values of adhesive systems did not infl uence signifi cantly their shear bond
strength to enamel or dentin.
Key Words: Dentin, enamel, one-step self-etch adhesives, bond strength