Thesis (M.Sc.) - Cairo University - Faculty of Oral and Dental Medicine - Department of Operative Dentistry

In this experimental study, two different restorative resin composite materials were used for restoring endodontically treated upper premolars with or without post placement (different techniques) on the fracture resistance of endodontically treated upper premolars. One adhesive system (Excite F Dsc Soft touch) and two different resin composites restorative material (ventura similux shade A3.5 and multi core flow shade A3) were used. A total of 60 single rooted sound human premolars free from visible cracks and other defects were selected for this study. The selected 60 single rooted premolars were mounted in acrylic resin blocks. Endodontic treatment was preformed for all specimens. Then they were randomly divided into two equal groups of 30 specimens each, according to the type of restoration used, either light cured microhybird resin composite (Ventura similux, Madespa S.A.) or dual cured resin composite (Multicore flow, Ivoclar Vivadent). Each group was subdivided into two equal groups of 15 specimens each according to restoration technique, the first subgroup was restored directly with the resin composites without post, and the second subgroup was restored with resin composites and fiber post. Universal Testing Machine (Lloyd, ametek.inc) with Nexygen operating software was used for the load testing.The fragments of each spacemen were collected to be examined under magnifying lens 6x magnification (carsonR magnilook), in order to define the mode of failure

Issued also as CD