OBJECTIVETo test the effects of different surface treatments on the adhesive strength between POPO fiber post and resin cement.

METHODS50 fiber posts were divided into 5 groups at random according to different surface treatments. Group A: Control group, no treatment. Group B: Silanization for 60 s. Group C: Etching for 30 s. Group D: Etching for 60 s. Group E: Etching for 120 s. Crowns of 45 fresh premolars were removed and assigned randomly to 5 test groups. After bonding and embedding the retentive force of the samples were tested by an universal testing machine. The morphology of the post surface was observed by a scanning electron microscope (SEM).

RESULTSThere were significant differences among the effects of different surface treatments on the adhesive strength between POPO fiber post and resin cement (P < 0.05). Group D showed the highest adhesivestrength (207.33 +/- 7.58) N. There was significant different between group D and E (P = 0.027), but there was not significant difference between group D and C (P = 0.112). Significant changes of post surface after different treatments were discovered by SEM. Surface roughness and area of fiber exposure increased.

CONCLUSIONThe adhesive strengths have been enhanced after conducting different surface treatments on the fiber posts.