title: The effect of two post-space preparation techniques on the seal of resilon and gutta-percha obturation materials.
abstract: BACKGROUND
  The aim of this study was to compare the effect of post space preparation with Gates Glidden drills or hand files on the sealing ability of gutta-percha or Resilon obturation materials.
  
  
  METHODS
  One-hundred and four single-rooted human teeth were instrumented and divided into four experimental groups (n=21 each) and two groups of positive and negative control (n=10). Forty-two roots of experimental groups were obturated with gutta-percha and Dorifill sealer; and 42 roots with Resilon/Epiphany self-etch using lateral compaction technique. Each gutta-percha or Resilon group was divided into two subgroups (n=21) and post-space prepared with either Gates Glidden drills or hand files and chloroform. After post space preparation, 5 mm of apical gutta-percha or Resilon was left intact. The whole system was sterilized with gamma-rays. Saliva leakage was tested using a split-chamber model. Specimens were monitored every 24 hours for 30 days. The data were analyzed using log-rank test and Cox regression analysis.
  
  
  RESULTS
  There were no significant differences between the sealing ability of gutta-percha and Resilon. Furthermore, no significant difference was found between two different methods of post space preparation (P>0.05).
  
  
  CONCLUSIONS
  Under the limitations of this ex vivo study, there were no significant differences between the sealing ability of Resilon and gutta-percha after post space preparation using Gates Glidden drills or hand files with the aid of chloroform.
authors.affiliation: Department of Endodontics, School of Dentistry/Dental Research Center, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Kazem
authors.initials: K
authors.lastname: Ashofteh Yazdi
authors.forename: Hasan
authors.initials: H
authors.lastname: Razmi
authors.forename: Sholeh
authors.initials: S
authors.lastname: Ghabraei
authors.forename: Noushin
authors.initials: N
authors.lastname: Shokouhinejad
authors.forename: Marzieh
authors.initials: M
authors.lastname: Aligholi
authors.forename: Saeed
authors.initials: S
authors.lastname: Rahmani
keywords: Gutta-Percha; Leakage; Post Space; Resilon; Solvents