title: Push-out bond strength of fiber posts luted with unfilled resin cement.
abstract: OBJECTIVE
  The study evaluates the behavior of different adhesive systems and resin cements in fiber post placement, with the intent to clarify the possible role of unfilled resin as a luting material for fiber posts.
  
  
  METHODS
  Two luting agents (Dual-Link and Unfilled Resin) for cementing fiber posts into root canals were applied either with All-Bond 2 or One-Step Plus, or without an adhesive system, and challenged with the push-out test. Slices of roots restored with posts were loaded until post segment extrusion in the apical-coronal direction. Failure modes were analyzed under SEM.
  
  
  RESULTS
  Push-out strength was significantly influenced by the luting agent (p < 0.05), but not by the bonding strategy (p > 0.05). The best results were obtained in combination with Unfilled Resin with One-Step Plus. Dual-Link groups failed mainly cohesively within the cement, while Unfilled Resin demonstrated more adhesive fracture at the post interface.
  
  
  CONCLUSIONS
  The results of this study support the hypothesis that adhesive unfilled resin application is essential for achieving high bond strength to radicular dentin.
authors.affiliation: Department of Operative Dentistry, University of São Paulo, Bauru School of Dentistry, Bauru, Brazil. carcarvalho@usp.br
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Carvalho
authors.forename: Francesca
authors.initials: F
authors.lastname: Monticelli
authors.forename: Amerigo
authors.initials: A
authors.lastname: Cantoro
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Breschi
authors.forename: Marco
authors.initials: M
authors.lastname: Ferrari