title: Influence of cement type and thickness on polyfiber post adhesion.
abstract: BACKGROUND
  To evaluate the effect of two different post space diameters and related resin cement film thicknesses on the bond strength of a polyfiber post.
  
  
  METHODS
  A total of 48 premolars were randomly divided into two according to the post space diameter: 1.1 mm and 1.5 mm. Then each group was divided into three sub-groups according to luting cement used: RelyX U100, Panavia F2.0/ED primer, Clearfil SA cement. Spirapost was then luted into the canal using luting cements. Two slices were obtained from each root specimen. Push-out tests were performed. Data was analyzed with Kruskal-Wallis and Connover post-hoc and Mann-Whitney U-test (P < 0.05).
  
  
  RESULTS
  Push-out bond strength was found to vary significantly according to type of adhesive system and post space diameter size (P < 0.05). The self-adhesive resin cement RelyX U100 had significantly higher bond strengths compared with the other adhesive system (P < 0.05). The self-etch adhesive system (Panavia F2.0) showed significantly lower bond strengths compared with the other systems (P < 0.05). There was a significant interaction between the luting systems and post space diameter (P < 0.05).
  
  
  CONCLUSIONS
  The increases in post space diameter significantly reduced the bond strength of Spirapost to root dentine for both groups.
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Hacettepe University, Sihhiye 06100, Ankara, Turkey.
authors.forename: Emel
authors.initials: E
authors.lastname: Uzunoğlu
authors.affiliation: Department of Endodontics, Bulent Ecevit University, Zonguldak, Turkey.
authors.forename: Sevinç Aktemur
authors.initials: SA
authors.lastname: Türker
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Hacettepe University, Sihhiye 06100, Ankara, Turkey.
authors.forename: Zeliha
authors.initials: Z
authors.lastname: Yilmaz
keywords: Bond strength; luting cement; self-adhesive resin cement; spirapost