title: Detectability of residual Epiphany and gutta-percha after root canal retreatment using a dental operating microscope and radiographs--an ex vivo study.
abstract: OBJECTIVE
  To compare the detectability of residual Epiphany and gutta-percha after root canal retreatment using a dental operating microscope and radiographic examination with the residual area measured after rendering the roots transparent.
  
  
  METHODS
  Sixty extracted single-rooted maxillary central incisor teeth were enlarged to apical size 40. Thirty canals were filled using vertically compacted Epiphany, the remainder were filled with vertically compacted gutta-percha and AH Plus sealer. After re-instrumentation to apical size 50, radiographs of the roots were taken in buccolingual and mesiodistal direction. Residual filling material was categorized by three observers using the radiographs and a dental operating microscope. The area of remaining material that was made visible by radiographs was measured with the aid of a computer image analysis programme. After clearing the roots, areas of residual filling material on the root canal wall were measured using a microscope.
  
  
  RESULTS
  Computer image analysis of the radiographs showed significantly smaller areas of remaining gutta-percha and Epiphany compared with the analysis of the transparent teeth that revealed only one absolutely clean root (Epiphany). Especially in the gutta-percha group, the scores determined by the observers using radiographic examination gave an over-optimistic impression of cleanliness compared with the scores determined by the visualization through the microscope.
  
  
  CONCLUSIONS
  Especially for remaining gutta-percha, the operating microscopes provided better detection of residual root filling material in retreated maxillary incisor teeth.
authors.affiliation: Department of Operative Dentistry and Periodontology, Albert-Ludwigs-University, Freiburg, Germany. joerg.schirrmeister@uniklinik-freiburg.de
authors.forename: J F
authors.initials: JF
authors.lastname: Schirrmeister
authors.forename: P
authors.initials: P
authors.lastname: Hermanns
authors.forename: K M
authors.initials: KM
authors.lastname: Meyer
authors.forename: F
authors.initials: F
authors.lastname: Goetz
authors.forename: E
authors.initials: E
authors.lastname: Hellwig
mesh_terms: D003786:Dental Pulp Cavity / Q000000981:diagnostic imaging / Q000473:pathology*; D004853:Epoxy Resins / Q000737:chemistry; D006171:Gutta-Percha / Q000737:chemistry*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007180:Incisor; D008853:Microscopy / Q000295:instrumentation; D015588:Observer Variation; D011861:Radiography, Dental; D019233:Retreatment; D012387:Root Canal Filling Materials / Q000737:chemistry*; D018915:Root Canal Preparation / Q000379:methods; D012390:Root Canal Therapy / Q000379:methods*; D013499:Surface Properties
chemical_list: D004853:Epoxy Resins; D012387:Root Canal Filling Materials; C486893:epiphany sealer; C534916:epoxy resin-based root canal sealer; D006171:Gutta-Percha