Journal of Dental Research, Vol 61, 412-418, Copyright © 1982 by International & American Associations for Dental Research Online Journals
The use of an intermediate resin in the acid-etch procedure: retentive strength, microleakage, and failure mode analysis
A. P. Prevost, J. L. Fuller and L. C. Peterson
Three composite resin systems, one conventional (Concise) and two
microfilled (IsoPast and Silar), used with and without an intermediate
resin (Concise Enamel Bond), were evaluated with and without thermal stress
for in vitro retentive strength and sealing ability to acid-etched human
enamel. All three materials yielded significantly different shear strength
values. The use of an intermediate resin significantly improved both the
shear strength and resistance to microleakage of Silar, while no
differences were observed for Concise and IsoPast. The thermocycling
procedure did not generally or consistently affect the results. The failure
mode of the three acid-etched composite resins was studied by evaluation of
the failure surface and by describing the percentage of enamel, composite,
and interface which were present. The use of an intermediate resin did not
significantly influence the failure mode, and the correlation between the
failure mode and retentive strength, although significant was low. The
study confirmed the importance of adequate wetting action of a resin on the
etched enamel to ensure proper bonding.
