Abstract: Objective: To analysis different fiber post surface treatments on fracture strength of roots after restoration, and to provide a reference basis for clinical fiber post surface treatment. Methods: Sixty fiber post were randomly divided into three groups: control group, sandblasting group, and hydrogen peroxide acid group. All fiber posts were fixed in the roots in vitro using the same resin and restored with full crown. After treated with the same simulation environment with cold and hot, the flexural crack strength was tested. Results: There was no significant difference on the in vitro teeth length, root length, and neck buccolingual diameter and mesiodistal diameter of three groups, no matter surface treatment method. The most frequent fracture sites after loading was happened at cervical 1/3, which indicated no relationship existed between surface treatment and fracture location and mode. Sandblasting group and hydrogen peroxide treatment group had higher fracture strength than the control group (P<0.05), however, no difference between sandblasting group and hydrogen peroxide group. Conclusion: Sandblasting and hydrogen peroxide treatment can both enhance the fracture strength of fiber post. Surface treatment has no relationship with the fracture mode of fiber post.

Key words: Fiber post, Sandblasting, Hydrogen peroxide, Flexural strength