الفهرس 
Composition of dental composite resins:
d. Classification according to clinical applications and functional requirements:Only 14 pages are availabe for public view
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Abstract
A total of thirty non-carious human maxillary premolars teeth were mounted 2mm below the cement - enamel junction in acrylic blocks. Trapezoidal class V cavities were prepared on the buccal surface of each tooth (mesio -distal width of 3 mm occlusally & 2.5 mm cervically, a length of 2.5 mm occluso- gingivally and a depth of 1.5mm). The gingival margins were located 1 mm apical to the cemento-enamel junction. All the cavity margins were not beveled. Flowable composite (Herculite XRV ultra flow), self- adhering flowable composite (Vertise Flow) and a nanohybrid composite (Herculite XRV ultra) were applied following their manufacture instructions, in groups I, II&III respectively. Optibond All‐In‐ One adhesive was applied in groups I&III while Vertise Flow was applied directly without adhesive. Specimens were subjected to 500 thermal cycles from 5o to 55 oC with 30 seconds(s) dwell time, and 15 s transfer time. They were then examined under stereomicroscope at 40x magnification to determine the marginal gap width. All specimens were then sectioned buccolingually into two sections using a microtome to detect and measure the internal gap width along the restoration/ tooth interface. The recorded data was collected, tabulated, and statistically analyzed using SPSS version 25.