title: Qualitative SEM/EDS analysis of microleakage and apical gap formation of adhesive root-filling materials.
abstract: OBJECTIVE
  The aim of this study was to compare the correspondence between gap formation and apical microleakage in root canals filled with epoxy resin-based (AH Plus) combined or not with resinous primer or with a dimethacrylate-based root canal sealer (Epiphany).
  
  
  METHODS
  Thirty-nine lower single-rooted human premolars were filled by the lateral condensation technique (LC) and immersed in a 50-wt% aqueous silver nitrate solution at 37ºC (24 h). After longitudinal sectioning, epoxy resin replicas were made from the tooth specimens. Both the replicas and the specimens were prepared for scanning electron microscopy (SEM). The gaps were observed in the replicas. Apical microleakage was detected in the specimens by SEM/energy dispersive spectroscopy (SEM/EDS). The data were analyzed statistically using an Ordinal Logistic Regression model and Analysis of Correspondence (α=0.05).
  
  
  RESULTS
  Epiphany presented more regions containing gaps between dentin and sealer (p<0.05). There was correspondence between the presence of gaps and microleakage (p<0.05). Microleakage was similar among the root-filling materials (p>0.05).
  
  
  CONCLUSIONS
  The resinous primer did not improve the sealing ability of AH Plus sealer and the presence of gaps had an effect on apical microleakage for all materials.
authors.affiliation: School of Dentistry, Federal University of Maranhão, São Luiz, MA, Brazil. sosocarvalho@usp.br
authors.forename: Soraia de Fátima Carvalho
authors.initials: Sde F
authors.lastname: Souza
authors.forename: Carlos
authors.initials: C
authors.lastname: Francci
authors.forename: Antonio C
authors.initials: AC
authors.lastname: Bombana
authors.forename: Silvia
authors.initials: S
authors.lastname: Kenshima
authors.forename: Lúcia P
authors.initials: LP
authors.lastname: Barroso
authors.forename: Liz Z
authors.initials: LZ
authors.lastname: D'Agostino
authors.forename: Alessandro D
authors.initials: AD
authors.lastname: Loguercio
mesh_terms: D003763:Dental Leakage / Q000209:etiology*; D004853:Epoxy Resins / Q000737:chemistry*; D006801:Humans; D016015:Logistic Models; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D011897:Random Allocation; D012387:Root Canal Filling Materials / Q000737:chemistry*; D012389:Root Canal Obturation / Q000379:methods*; D013052:Spectrometry, X-Ray Emission; D019227:Tooth Apex / Q000737:chemistry*
chemical_list: D004853:Epoxy Resins; D012387:Root Canal Filling Materials; C486893:epiphany sealer; C534916:epoxy resin-based root canal sealer