الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
This in vitro study was carried out to assess the microtensile bond strength of
resin composite to dentin pretreated by antimicrobial silver nanoparticle and tested at two different aging times (24 hours and 3 months). Methods: Spherical silver nanoparticles were
synthetized. 10 ml of 1% ethanolic solution of Polyvinyl Pyrrolidone and 0.2 ml Silver Nitrate powder were mixed in a closed test tube containing 25ml distilled water and placed
in a microwave oven that was operated at 1000W and frequency 2450MHz for 5 seconds.
The colorless solution instantaneously turned to the characteristic yellow color, indicating the formation of silver nanoparticles. The occlusal surface of 60 human molars were ground
flat to expose both the superficial and deep dentin levels in each tooth. Half of the specimens were treated with silver nanoparticles after etching and the other half works as a control.
Adper Single Bond 2 adhesive system was applied and cured followed by build-up using a nano-filled resin composite (Filtek Z350XT). Each specimen was sectioned to produce 1mmdiameter sticks used for the test. Resin dentin interface were analyzed using Environmental Scanning Electron Microscope. Results: Both superficial and deep dentin level, non-treated
with nanoparticles recorded statistically significant higher microtensile bond strength mean
value than that treated ones after 24 hours aging period (p > 0.05). With the specimens tested after 3 months aging , superficial dentin level, treated with nanoparticles recorded statistically significant higher microtensile bond strength mean value than that non- treated ,while with the deep dentin level, statistically non-significant difference in the bond strength
between treated and non-treated specimens appeared (p > 0.05).Conclusion: Silver nanoparticles are a promising antibacterial pretreatment agent that didn’t antagonize
penetration of resin tags into dentinal tubules. Spherical shape silver nanoparticles in ethanol
based solution did not hinder bonding of resin composite to dentin.