الفهرس 
Fiber reinforced composite dowelsOnly 14 pages are availabe for public view
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Abstract
This in vitro study was performed to evaluate the fracture resistance of flared root canals of endodontically treated upper central incisors restored with hybrid ceramic dowel and core (experimental group) in comparison with cast base metal dowel and core (control group).Twenty human extracted intact upper central incisors of an average similarity in size, shape and root morphology were used in this study.Crowns of the selected teeth were sectioned perpendicular to the long axis 2-mm coronal to the cemento-enamel junction to provide root lengths of 14-mm.The root canals were manually prepared and instrumented to a working length of 1-mm above the apical foramen to size 40 K-file. Canals were obturated with a gutta-percha cones matching the last file size and a MMseal resin sealer using lateral condensation technique. In order to obtain a simulated over flared canals, the root canals were enlarged with the size 6 drill supplied by the manufacturer of I-post system coupled with low speed hand piece leaving specimens with 9-mm dowel space length. After preparation of the finish line, the coronal dentinal extension was modified using a diamond bur in order to obtain a 2-mm circumferential ferrule on the remaining sound tooth structure.