Abstract: Objective: To evaluate the effect of simplified ethanol wet bonding and different treatments on the surface of post space wall, so as to provide reference for the application of fiber post bonding. Methods: Fifty-two single root canal teeth were collected. The crowns of teeth were sectioned 2 mm above the cementoenamel junction. After the root canal treatment, post space was prepared. The specimens were randomly divided into 4 groups according to different solvent treatment. Group A: distilled water irrigation (control group); group B: irrigation with 5.25% sodium hypochlorite (NaClO) solution; group C: irrigation with 17% EDTA solution; group D: irrigation with 5% NaClO followed by 17% EDTA solution. Each group was randomly assigned into two subgroups according to different substrate conditions (water-wet or simplified ethanol-wet). Each specimen was sectioned into thick slises. The push-out test was performed. The dentin surface and bonding interface were examined under SEM. The fracture mode were analyzed. Results: Compared with control group, the smear layer was removed to varying degrees in the other three groups. The result of bond strength was: C>B>D>A and ethanol-wet>water-wet (P<0.05). Conclusion: Irrigation with 5% NaClO followed by 17%EDTA solution can eliminate the smear layer effectively. The application of simplified ethanol wet bonding technology can get higher bonding strength of fiber post in this experiment.

Key words: Fiber post Smear, layer Simplified ethanol-wet bonding , Bond strength