title: Retreatment efficacy of the Epiphany soft resin obturation system.
abstract: OBJECTIVE
  To assess the efficacy of retreatment of canals filled with the Epiphany System with and without solvent, with particular reference to the extent of canal enlargement during retreatment.
  
  
  METHODS
  Sixty roots with canals prepared to apical size 45 were embedded in resin blocks and sectioned vertically. Digital micrographs of canal walls were captured. Roots were re-assembled and filled with Epiphany/Resilon (experimental) or gutta-percha/AH Plus (control). After 8 weeks, canals were retreated to size 45 with or without chloroform, and the time recorded. Roots were split, imaged, re-assembled, retreated to size 55, split and imaged. Root-filling residue, traced at three canal levels, was expressed as percentage of canal surface.
  
  
  RESULTS
  Residue percentage was greater (t-test, P < 0.01) in the experimental group than in the control. Most residue in all specimens was in the apical third (ANOVA, P < 0.01). Chloroform and enlargement to size 55 decreased residue in both groups (t-test, P < 0.01). Retreatment time was longer in the experimental group (P < 0.05), and reduced by chloroform in both groups (P < 0.05).
  
  
  CONCLUSIONS
  The Epiphany System was retreatable with and without chloroform, with lesser efficacy than gutta-percha and AH Plus sealer.
authors.affiliation: Department of Endodontics, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada.
authors.forename: A
authors.initials: A
authors.lastname: Hassanloo
authors.forename: P
authors.initials: P
authors.lastname: Watson
authors.forename: Y
authors.initials: Y
authors.lastname: Finer
authors.forename: S
authors.initials: S
authors.lastname: Friedman
mesh_terms: D000704:Analysis of Variance; D002725:Chloroform / Q000627:therapeutic use; D004853:Epoxy Resins / Q000737:chemistry; D006171:Gutta-Percha / Q000737:chemistry; D006801:Humans; D019233:Retreatment / Q000379:methods; D012387:Root Canal Filling Materials / Q000737:chemistry / Q000627:therapeutic use*; D012389:Root Canal Obturation / Q000379:methods*; D012997:Solvents / Q000627:therapeutic use
chemical_list: D004853:Epoxy Resins; D012387:Root Canal Filling Materials; D012997:Solvents; C486893:epiphany sealer; C534916:epoxy resin-based root canal sealer; D002725:Chloroform; D006171:Gutta-Percha