An in vitro Evaluation of the Effect of Four Dentin Bonding System on the Bond Strength between Quartz Fiber Post and Composite Core

Statement of problem: a strong bond of fiber post to resin core, as well as to dentin would critically ensure the durability of restorations in endodontically treated teeth. purpose: the purpose of this study was to evaluate the effect of etch-and-rinse dentin bonding systems on the bo nd strength between resin core and fiber post after application of 24% hydrogen peroxide. materials and method: 24 fiber posts (rtd; st. egèven, france) were treated with 24% hydrogen peroxide for 10 minutes. they were randomly divided into 4 groups (n=6) based on the bonding agent used: group p: prime&bond, group o: one step, group s: single bond and group e: excite. each group was prepared according to the manufacturer’s instructions. for all posts, a flowable composite core (æliteflo; bisco, usa) was built-up over the bonded area. each specimen was sectioned to produce 2 sticks, 1mm in thickness and underwent microtensile bond strength (μtbs). data were analyzed using one-way anova at the 0.05 level. the fractured surfaces of all sticks were evaluated by stereomicroscope (× 20). scanning electron microscopy(sem) assessment of two sticks from each group was performed to evaluate the surface morphology. results: the means and sds of μtbs were: group p: 10.95±1.74; group s: 10.25±2.39; group e: 9.52±2.07; and group o: 9.12±1.34. there was no statistically significant difference in bond strength means between the groups tested (p> 0.05). conclusion: the results of this study indicated the bonding agents used had no significant influence on the bond strength of fiber post to composite core.