The effect of silane on the bond strengths of fiber posts

Esthetic posts have been developed to maximize the foundation of esthetic restorations. The purpose of this study was to evaluate the effect of silane on the bond strength of three fiber-reinforced resin posts (fiber posts).

Fifty-four extracted human maxillary central incisors and canines were endodontically treated. D.T. Light Post (DT, Bisco), FRC Postec (FR, Ivoclar Vivadent), and ParaPost Fiber White (PP, Coltène/Whaledent) were inserted using the resin adhesive system provided by the respective manufacturer. For half of the specimens in each group, the fiber posts were treated with a silane solution (Monobond S, Ivoclar Vivadent). A push-out test was performed on three different sections of each root to measure bond strengths. Data were analyzed with ANOVA and Bonferroni's post hoc test at P<0.05.

The use of silane did not result in any statistically significant difference at any level of the root. Silane did not result in any significant different bond strengths (MPa) for each of the posts. When the data were pooled, the use of silane did not result in statistically significant different bond strengths at P>0.403: No silane=12.7+/-8.4; Silane=14.1+/-7.0. The coronal third of the root (17.5+/-6.7) resulted in statistically greater bond strengths than the medium third (12.9+/-6.8) and than the apical third (9.8+/-7.3) at P<0.002 and P<0.0001, respectively. The medium third and the apical third resulted in no statistically significant different bond strengths from each other at P>0.07. The type of post did not result in statistically significant different bond strengths at P>0.417: DT=14.7+/-6.8 MPa; FR=13.3+/-6.6 MPa; PP=12.2+/-6.6 MPa.

The use of a silane coupling agent did not increase the push-out bond strengths of the three fiber posts used in this study. All posts bonded to root dentin at the same magnitude. Bonding is more predictable at the most coronal level of the root.