الفهرس 
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Abstract
This study was conducted to evaluate the SBS durability and
nanoleakage of the different chemical surface treatments on resin cement to
chair side indirect resin composite material.
For shear bond strength testing, 200 resin composite discs and 200
cylinders were randomly divided into 20 experimental groups (n = 10)
according to the two experimental factors investigated in this study: Factor 1:
The resin composite surface treatment, 10 groups and Factor 2: The storage
time, 2 groups. Before bonding, the fitting surface of each resin composite
specimen was treated with each chemical surface treatment as specified.
Resin composite cylinders were bonded to the discs using a dual cure resin
cement and light cured. Half of the bonded specimens were stored for 24
hours and the other half was stored for 1-year. SBS test was run at a
crosshead speed of 0.5 mm/min. For nanoleakage testing, specimens were
assigned into 20 groups (n = 2) as for SBS testing. Specimens were
evaluated using SEM operated in the backscattered mode to detect dye
penetration. For resin composite/resin cement/resin composite interface and
surface topography, specimens were examined using SEM. Surface
microhardness was evaluated using Vickers microhardness tester. Statistical
analysis was performed using Two-Way ANOVA/ Turkey’s HSD post hoc
test.
The results showed that Two-Way ANOVA revealed that surface
treatment, storage time and their interactions showed a significant effect on
shear bond strength (P<0.001). For 24 hours, only, the HP+S showed the
highest significant SBS values among all tested groups. All groups were
shown statistically significant DROP in SBS after 1-year storage period.
Nanoleakage results showed tracer penetration at the resin composite resin
Summary and Conclusions
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cement interface was not observed in all of the tested groups except,
specimens treated with HF acid/HF acid+S and stored for 1-year. SEM
evaluation of adaptation of resin composite/resin cement interface reveled
the intimate adaptation of all experimental groups. Surface topography
demonstrated the ability of all the tested surface treatment, except the PP
surface treatment, to alter resin composite surface when compared to the NT
groups. Surface microhardness testing showed that HF acid significantly
decreased surface microhardness compared to all tested groups. The PP
group showed statistically significant DROP in surface microhardness when
compared to the NT group.
Conclusions
Within the limitations of this study, the following conclusions could be
suggested:
1- Although, the different surface treatments improved the SBS of resin
cement to chair side resin composite used in this study compared to
NT, the PP surface treatment solely or with silane did not revealed
any positive effect on the SBS.
2- Storage in water for 1-year negatively affected the SBS durability
regardless of the type of chemical treatment used.
3- The application of silane over the chemically treated resin composite
surfaces did not improve the durability of the SBS. Its effect was
dependent on the type of chemical treatment used.
4- The intimate adaptation of resin cement to resin composite was
evident even after 1-year storage period, with no nanoleakage, except
Summary and Conclusions
85
for the HF and HF+S groups stored for 1-year, which exhibited silver
nitrate depositions along the interface after 1-year storage time.
5- The use of HF acid dramatically decreased the surface microhardness
compared to all tested treatments.
6- Alteration of surface morphology was clear for all the chemical
surface treatments used in this study compared to the NT group,
except for the PP surface treatment, which showed no surface
morphology alteration.
It seems that chemical surface treatments of chair side resin
composite material used in this study can be adopted as effective, easy
and non-costly alternative to more sophisticated treatments. The use of
Potassium Permanganate to treat highly filled resin composite should be
reconsidered in future studies