title: Comparison of Endodontic Medicaments on Bond Strength of Fiber Post to Root Dentin Using Resin Cement.
abstract: BACKGROUND
  Endodontic irrigants and medicaments may affect the bond strength of intracanal posts to root dentin.
  
  
  OBJECTIVE
  The aim of this study was to compare the effect of calcium hydroxide (Ca(OH)2) and 2% chlorhexidine gel (CHX) on bond strength of fiber post cemented with resin cement to root dentin.
  
  
  METHODS
  This in vitro experimental study was conducted on 36 mandibular premolars. Canals were prepared using the step back technique. After root canal irrigation, the teeth were divided into three groups of 12. Ca(OH)2paste and CHX gel were used as intracanal medicaments in the first and second groups respectively. No intracanal medicament was used in the third group (control group). Access cavities were then sealed and the teeth were incubated for one week. The root canals were then filled using gutta percha and AH26 sealer and the teeth were incubated for 72 hours. Tooth crowns were then cut at the level of the cementoenamel junction and intracanal posts were placed. The teeth were mounted in auto-polymerizing acrylic resin, and incubated for one week .They were then sectioned into 1.5mm thick slices from their coronal surface using a fully automated cutting machine, and subjected to push-out test until failure. The load at debonding was recorded and data were analyzed using one-way ANOVA, post-hoc test and t-test. The coronal margin of the root was at the level of the surface of acrylic resin in the mold.
  
  
  RESULTS
  The mean bond strength was 4.45 MPa in the Ca(OH)2, 2.45 MPa in the CHX and 2.48 MPa in the control group. The difference in this regard was statistically significant among groups (p= 0.04). The Ca(OH)2group had significant differences with the CHX and control groups (p= 0.03 andp= 0.02, respectively). The difference between the CHX and control groups was not significant (p= 0.974).
  
  
  CONCLUSIONS
  Based on the results, Ca(OH)2increased the bond strength of fiber post to root dentin but 2% CHX had no effect on bond strength.
authors.affiliation: Dept. of Endodontics, Dental School (Faculty), Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Zare Jahromi
authors.affiliation: Dept. of Operative Dentistry, Dental School (Faculty), Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran.
authors.forename: Mehrdad
authors.initials: M
authors.lastname: Barekatain
authors.affiliation: Dentist, Shiraz, Iran.
authors.forename: Shirin
authors.initials: S
authors.lastname: Ravanbod
authors.affiliation: Dept. of Endodontics, Dental School (Faculty), Shahrekord University of Medical Sciences, Shahrekord, Iran.
authors.forename: Parisa
authors.initials: P
authors.lastname: Ranjbarian
authors.affiliation: Post Graduate Student, Dept. of Endodontics, Dental School (Faculty), Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran.
authors.forename: Sara
authors.initials: S
authors.lastname: Kousehlar
keywords:  Calcium Hydroxide ;  Fiber Post ;  Resin Cement; Chlorhexidine 