Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 15 4 2018 08 19 222 229 EN Hamid Jalali Assistant Professor, Department of Prosthodontics, Tehran University of Medical Sciences, Tehran, Iran Farzaneh Farid Assistant Professor, Department of Prosthodontics, Tehran University of Medical Sciences, Tehran, Iran Sudabeh Kulivand Postgraduate Student of Prosthodontics, Department of Prosthodontics, Tehran University of Medical Sciences, Tehran, Iran Saeed Nokar Associate Professor, Department of Prosthodontics, Tehran University of Medical Sciences, Tehran, Iran Kosar Dadgar Assistant Professor, Department of Prosthodontics, Mazandaran University of Medical Sciences, Mazandaran, Iran 2017 11 29 2018 06 16 Objectives: The aim was to investigate the effect of intracanal irrigants and agents on the bond strength of intraradicular fiber posts to dentin. Materials and Methods: Root canals of 72 decoronated single-rooted premolars were cleaned, shaped, and obturated with gutta-percha and AH26. The specimens were incubated at 37oC and 100% humidity for seven days. Next, the coronal 10 mm of the canals were prepared to receive size 2 D.T. Light fiber post, and the specimens were randomly allocated into six groups according to the irrigants used after post space preparation: normal saline (control group), 5.25% sodium hypochlorite (NaOCl)/15 seconds, 17% ethylenediaminetetraacetic acid (EDTA)/60 seconds, 2% chlorhexidine (CHX)/5 minutes, MTAD/5 minutes, and acid-etching/15 seconds. All canals were rinsed with normal saline and dried. Fiber posts were cemented using Panavia F2.0. After 24 hours, two mid-root slices of 1mm thickness were obtained from each specimen. Push-out bond strength test was performed in a universal testing machine at 0.5mm/minute. The maximum applied load was recorded, and the bond strength was calculated in megapascal (MPa). Data were analyzed by one-way analysis of variance (ANOVA) and Tukey's test.  Results: The mean shear bond strengths of etched (53.21±12.11 MPa), MTAD (52.47±14.75 MPa) and EDTA (49.08±10.19 MPa) groups were significantly higher than that of the control group (39.82±10.04 MPa). The difference was marginally significant for CHX group (49.8±13.57 MPa) and not significant for NaOCl group (47.15±17.64 MPa). Conclusions: Etching or irrigating the root canals with MTAD or EDTA after post space preparation increases the bond strength of Panavia F2.0 to dentin. https://fid.tums.ac.ir/index.php/fid/article/view/2257 https://fid.tums.ac.ir/index.php/fid/article/download/2257/1014