الفهرس 
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Abstract
This study was conducted to evaluate the effect of different bonding protocols on the push-out bond strength of fiber reinforced composite post to radicular dentin using two flowable core build up resin composites. In total, 72 single rooted premolar teeth were randomly assigned into 6 groups (n=12) according to the two experimental factors investigated in this study. Factor 1: The bonding protocols and Factor 2: The type of flowable core build-up resin composite. After the preparation of the post space, the self-etching adhesive was applied and was light cured according to manufacturer time, doubling the manufacturer recommended time or left to be cured with resin cement. All specimens were subjected to push-out bond strength testing using a Universal Testing Machine moving at crosshead speed of 0.5 mm/min. Representative samples from each group were randomly selected to evaluate the adaptation of the core build-up material to radicular dentin and post under SEM. Two-Way ANOVA revealed that the cement type and the bonding protocol had no significant effect on push-out bond strength of fiber post to dentin (P=0.089 and P=0.408 respectively), while their interactions showed significant effect (P<0.0001). The failure mode analysis showed that the failures observed were 56.9% adhesive, 43.1% mixed and 0% cohesive in dentin. In conclusion, in all bonding protocols, the type of cement has an influence on the bonding of fiber post to root canal dentin.
Under the limitations of this study, the following conclusions could be suggested:
1- Doubling the light curing time has a positive influence in bonding of fiber post to root canal dentin using the dual-cure core build-up resin cement. On the contrary, it shows a negative influence with chemical-cured core build-up resin cement.
2- In all bonding protocols, the type of cement has an influence on the bonding of fiber post to root canal dentin.
3-Resin cement type and bonding protocol have an influence on the bond strength of fiber post to root canal dentin in different root regions.
4- It seems that adopting co-cure/self-cure resin cement combination technique improved the adaptation of cement/post/dentin in all root regions.