title: Effect of endodontic sealers on push-out bond strength of cemented fiber posts.
abstract: OBJECTIVE
  The purpose of this study was to compare the effect of eugenol-based and resin-based endodontic sealers on the push-out bond strengths of prefabricated fiber posts luted with different resin cements.
  
  
  METHODS
  Ninety prefabricated fiber posts were luted into extracted singlerooted teeth with one of three resin cements (Variolink II, ParaCore, or Rely X Unicem). Each group was subdivided into three groups with 10 teeth each. The first two groups were obturated with gutta percha and one of two eugenol-based endodontic sealers (Endofil or TubliSeal) each. The third group was obturated with gutta percha and (AH26) resin-based root canal sealer. Push-out tests were performed in a universal testing machine by applying a load speed at 0.5 mm/min by using a 1-mm-diameter metallic plunger which induced a load in an apical to coronal direction. The maximum value for post dislodgement (in Newtons) was recorded. Data were collected and statistically analyzed using two-way ANOVA and Tukey multiple comparison tests (α = .05).
  
  
  RESULTS
  The highest mean bond strength values were recorded for the AH26 sealer group (non-eugenol sealer) luted with Rely X Unicem resin cement (mean ± SD = 326.1 ± 66.1 N), while the lowest mean bond strength values were observed with posts luted with Variolink II resin cement into canals obturated with gutta-percha and Endofil (eugenol-based) sealer (90.3 ± 25.2 N). There was no significant difference between the means of push-out strengths for the Endofil and TubliSeal groups (P = .745).
  
  
  CONCLUSIONS
  Eugenol-based sealers (Endofil and TubliSeal) significantly reduced the push-out bond strength of prefabricated fiber posts luted with resin cement.
authors.forename: Ziad Nawaf
authors.initials: ZN
authors.lastname: Al-Dwairi
authors.forename: Khalil
authors.initials: K
authors.lastname: Aleisa
authors.forename: Edward
authors.initials: E
authors.lastname: Lynch
mesh_terms: D001641:Bicuspid; D001729:Bismuth / Q000737:chemistry; D001840:Dental Bonding / Q000379:methods*; D003799:Dental Stress Analysis; D004853:Epoxy Resins / Q000737:chemistry; D005054:Eugenol / Q000737:chemistry; D006171:Gutta-Percha / Q000737:chemistry; D006801:Humans; D066298:In Vitro Techniques; D011176:Post and Core Technique; D019279:Resin Cements / Q000737:chemistry*; D012387:Root Canal Filling Materials / Q000737:chemistry*; D012389:Root Canal Obturation; D012834:Silver / Q000737:chemistry; D014025:Titanium / Q000737:chemistry; D015035:Zinc Oxide-Eugenol Cement / Q000737:chemistry
chemical_list: D004853:Epoxy Resins; C483701:Rely X Unicem; D019279:Resin Cements; D012387:Root Canal Filling Materials; D015035:Zinc Oxide-Eugenol Cement; C074417:Endo-Fill; C103502:Variolink; D012834:Silver; D005054:Eugenol; C028044:epoxy resin AH-26; C048769:tubliseal; D006171:Gutta-Percha; D014025:Titanium; D001729:Bismuth