الفهرس 
Effect of endodontic treatment on the tooth structureOnly 14 pages are availabe for public view
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Abstract
Fiber reinforced posts have been widely used for restoration of endodonticaly treated teeth. Similarity in elastic behavior between fiber posts and the residual root dentin, decreases the rate of root fracture. The retention of fiber posts in roots depends on the bond strength between the post material and a resin luting agent, as well as the bond strength between the resin luting agent and post space dentin.
Several categories of cements and adhesives are available in the market have been proposed to bond fiber-reinforced posts to root canal dentin, including self adhesive resin cements, conventional cements and core buildup materials. Pretreatment of root dentin with dual or light cured adhesives is required prior to cementation with conventional cement or core buildup material. Some of these adhesives have a certain degree of incompatibility when used with dual cured cements, therefore new dual cured adhesives are produced which can overcome this problem.
In this study forty five single rooted teeth were used. Teeth were decoronated at the cementoenamel junction, then endodonticaly treated. Following post space preparation, the roots were divided into 9 groups (N=5) according to the method of post cementation: in group A the post was cemented using self-adhesive resin cement, in groups BLT and CLT dentin was pretreated with total etch light cured adhesive then the post was cemented using conventional cement in BLT and core buildup material in CLT. In groups BLS and CLS dentin was treated with self-etch light cured adhesive then the post was cemented using conventional cement in BLS and core buildup material in CLS.in groups BDT and CDT dentin was treated with total etch dual cured adhesive then the post was cemented using conventional cement in BDT and core buildup material in CDT. In groups BDS and CDS dentin was treated with self-etch dual cured adhesive then the post was cemented using conventional cement in BDS and core buildup material in CDS. The roots were subjected to Thermocycling, then the roots were sectioned into 3 sections.
The bond strength was evaluated using push out test. The failure mode was analyzed using stereo microscope.
Results showed that:
1. The conventional cement showed the highest mean push out bond strength (7.768 MPa) followed by the core build up material (5.822 MPa), self-adhesive resin cement showed the lowest mean push out bond strength (2.492 MPa).
2. Dual cured adhesives showed the highest push out bond strength (8.35 for total etch, 7.95 for self etch), total etch light cured adhesives showed the lowest bond strength (3.52 MPa).
3. The regional bond strength values were reduced significantly in apical post space.