title: Gas permeability: a new quantitative method to assess endodontic leakage.
abstract: OBJECTIVE
  The aim of this study was to evaluate a new endodontic leakage measurement method.
  
  
  METHODS
  Permeability was assessed measuring the gas flow passing through the root. Positive and negative tests were carried out to assess the validity of the method. We used glass capillaries for calibration (diameters of 15, 30, 40, 50 and 75 microm). The applicability of the method was assessed with human teeth using three sealing methods: GuttaFlow (GF) and a single cone; Pulp Canal Sealer (PCS) and a single cone; PCS and system B.
  
  
  RESULTS
  This method demonstrated to be highly reproducible as the standard deviation was approximately 1% on average with glass capillaries. Significantly higher leakage (p<0.05) was recorded for endodontic treatment with GF and single cone compared to PCS and single cone and PCS with system B.
  
  
  CONCLUSIONS
  Gas permeability is quantitative, sensitive, non-destructive and reproducible and seems appropriate for endodontic tests. It would participate in the indirect comprehension of leakage phenomena.
authors.affiliation: Bio-nano Laboratory, EA 4203, UFR d'Odontologie, Université Montpellier 1, Montpellier, France. Olivier@romieu.info
authors.forename: Olivier J
authors.initials: OJ
authors.lastname: Romieu
authors.forename: Bruno
authors.initials: B
authors.lastname: Jacquot
authors.forename: Sylvie
authors.initials: S
authors.lastname: Callas-Etienne
authors.forename: Pierre-Yves Collard
authors.initials: PY
authors.lastname: Dutilleul
authors.forename: Bernard
authors.initials: B
authors.lastname: Levallois
authors.forename: Frederic J G
authors.initials: FJ
authors.lastname: Cuisinier
mesh_terms: D000465:Algorithms; D003763:Dental Leakage / Q000517:prevention & control*; D004708:Endodontics / Q000295:instrumentation*; D019544:Equipment Failure Analysis / Q000295:instrumentation* / Q000379:methods*; D005740:Gases / Q000032:analysis*; D006801:Humans; D010539:Permeability; D012387:Root Canal Filling Materials
chemical_list: D005740:Gases; D012387:Root Canal Filling Materials