title: Fluoride varnish as root canal sealer: a scanning electron microscopy and bacterial penetration study.
abstract: BACKGROUND
  This study was carried out to evaluate the bacterial leakage of root canal fillings when cavity varnish containing 5% fluoride (Duraflur) was used as root canal sealer.
  
  
  METHODS
  Root canals of 88 straight single-rooted teeth were prepared. Eighty teeth were randomly divided into 3 experimental groups (n=20) and two positive and negative control groups of ten each. The roots in group I and II were obturated with gutta-percha and AH-26 sealer using lateral condensation technique. The root canal walls in group II were coated with a layer of varnish before obturation. In group III the canals were obturated with gutta-percha and fluoride varnish as the sealer. Enterococcus faecalis (E. faecalis) was used to determine the bacterial leakage during 90 days. The Kaplan Meier survival analysis was used for assessing the leakage and log rank test was used for pairwise comparison. The rest of eight single rooted teeth were selected for scanning electron microscopy (SEM) evaluation with 5000× magnification.
  
  
  RESULTS
  Leakage occurred between 20 to 89 days. Group III showed significantly less bacterial penetration than groups I and II (P=0.001 and P=0.011, respectively). However, there was no significant difference between group I and II (P>0.05). SEM evaluation showed that the varnish had covered all dentinal tubules.
  
  
  CONCLUSIONS
  The present study showed promising results for the use of fluoride varnish as root canal sealer but further in vitro and in vivo studies are needed.
authors.affiliation: Kerman Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran;
authors.forename: Masoud
authors.initials: M
authors.lastname: Parirokh
authors.affiliation: Private Practice, Tehran, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Talebizad
authors.affiliation: Oral and Dental Diseases Research Center, Kerman University of Medical Sciences, Kerman, Iran;
authors.forename: Farshid Reza
authors.initials: FR
authors.lastname: Forghani
authors.affiliation: The Research Center for Modeling in Health, Institute for Future Studies in Health, Kerman University of Medical Sciences, Kerman, Iran;
authors.forename: Ali Akabar
authors.initials: AA
authors.lastname: Haghdoost
authors.affiliation: Iranian Center for Endodontic Research, Research Institute of Dental Sciences, Shahid Beheshti University of Medical Sciences;
authors.forename: Saeed
authors.initials: S
authors.lastname: Asgary
authors.affiliation: Iranian Center for Endodontic Research, Research Institute of Dental Sciences, Shahid Beheshti University of Medical Sciences;
authors.forename: Mohammad Jafar
authors.initials: MJ
authors.lastname: Eghbal
authors.affiliation: Department of Endodontic, Dental School, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Jamileh
authors.initials: J
authors.lastname: Goddousi
keywords: Bacterial Leakage; Fluoride Varnish; Root Canal Sealer; SEM; Scanning Electron Microscopy