الفهرس 
Structure of Dental Hard TissuesOnly 14 pages are availabe for public view
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Abstract
This study was performed to evaluate fracture resistance of premolars restored with packable composite resin using different types of adhesive
systems. A total of fifty sound maxillary second premolars, were mounted in an acrylic block(2 mm below Cemento-Enamel Junction).Forty specimens received an operator prepared Class II MOD cavities with a 2 ± 0.2mm pulpal depth, 1.5 ± 0.2mm gingival width, 2 ± 0.2mm axial height, and parallel proximal walls with 3 ± 0.2mm buccolingual width. The samples were divided into five groups(10 each)as follows:group I: positive control group (intact teeth; without preparation and
restoration).group II: negative control group (prepared teeth without restoration) group III: prepared teeth and restored using Adper Single Bond Adhesive with Filtek™ Z350 XT packable composite resin group IV: prepared teeth and restored using Clearfil liner Bond F Adhesive with Filtek™ Z350 XT packable composite resin
group V: prepared teeth and restored using Single Bond Universal
Adhesive with Filtek™ Z350 XT packable composite resin Specimens then were subjected to thermo-cycling for 500 cycles, between 5°C and 55°C, with 20 seconds dwell time and 5-10 sec transfer time. After that, they were subjected to compressive axial loading by cross-head speed(0.5 mm/min),and were tested individually in a universal testing machine with a 4mm diameter steel sphere applied occlusaly on the buccal and lingual cusps of the tested restored and control specimens.