Author/Authors :
Najafi -Abrandabadi، Ahmad نويسنده 1Department of Restorative Dentistry, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran , , Najafi -Abrandabadi، Siamak نويسنده 2Department of Cariology and Comprehensive Care, NYU, College of Dentistry, New York, , , Ghasemi، Amir نويسنده Department of Restorative Dentistry, School of Dentistry, Shahid Beheshti University of Medical Sciences , , G. Kotick، Philip نويسنده Department of Cariology and Comprehensive Care, NYU, College of Dentistry, New York, ,
Abstract :
Background: Failures such as marginal discoloration and composite chipping are still the problems
of tooth-colored restorations on the substrate of enamel and porcelain, which some of these
problems are consequently as a result of failures in the bonding layer. Using fi lled resin has been
recently introduced to increase the bond strength of this layer. The aim of this study was to compare
the microshear bond strength (?-SBS) of composite resins to enamel incubated in periods of 24 h
and 9 months and porcelain with unfi lled resin and fl owable composites (fi lled resin).
Materials and Methods: In this in vitro study, two groups of 75 enamel samples with different
storage times (24 h and 9 months) and a group of 75 porcelain samples were used. They were
divided into 5 experimental groups of 15 samples in each. Composite cylinders in tygon tubes were
bonded on the surface of acid-etched enamel and pretreated porcelain. Wave, Wave MV, Wave HV,
Grandiofl ow and Margin Bond were used as bonding agents. The ?-SBS was measured at the speed
of 1.0 mm/min. The bond strengths were analyzed with one-way analysis of variance (ANOVA)
test followed by Tukey test. P < 0.05 was selected as the level of statistical signifi cance in this study.
Results: The results showed that for enamel (24 h), the ?-SBS of the Wave MV and Wave HV
groups were signifi cantly lower than the Margin Bond group. Tukey test indicated the absence of a
signifi cant difference between the ?-SBS of the Wave group and the Margin Bond group. However,
the ?-SBS of the Grandiofl ow group was signifi cantly higher than the one for the Margin Bond as
a bonding agent. In enamel (9 months), there was a signifi cant difference between the Grandiofl ow
and Margin Bond groups. Regarding bonding to the porcelain the one-way ANOVA test did not
show a signifi cant difference among the groups.
Conclusion: This study revealed that fl owable composites (fi lled resins) can be used instead of
unfi lled resins in bonding composite resins to enamel and porcelain substrates.
