The effect of the use of 2% chlorhexidine gel in post-space preparation on carbon fiber post retention.

Objective: Evaluate the bond strength of a resin cement used to lute carbon fiber posts, when drills and 4 different substances were used for the post-space preparation.

Study Design: Forty human canines were treated endodontically, and had a 10-mm length post space preparation. Four different substances were used with the drills: G1 -saline, G2 -2% chlorhexidine gel, G3 -EDTA/NaOCl, and G4 -xylene. Carbon fiber posts (C-Post) were cemented with Allbond2 and Hi-X. Then, the posts were dislodged by tensional forces.

Results: The groups of chlrohexidine (G2) and xylene (G4) obtained superior average values of bond strength at the 5% significance level (Parametric analyzes ANOVA/Tukey/Scheffe) differing statistically from the other groups. There was no statistical significant difference between groups 2 and 4.

Conclusion: Xylene and chlorhexidine gel are good substances for the post-space preparation but the second has the advantage of antimicrobial activity and low toxicity.