title: Resistance to vertical root fracture of endodontically treated teeth with MetaSEAL.
abstract: BACKGROUND
  The purpose of this in vitro study was to assess the influence of MetaSEAL and AH Plus on the resistance to vertical root fracture of endodontically treated teeth when either the matched-taper single-cone or lateral condensation technique was used.
  
  
  METHODS
  Ninety extracted single-canal mandibular premolar teeth were sectioned, leaving a standard root length of 13 mm. The buccolingual and mesiodistal diameters were measured, and the teeth were randomly divided into 6 groups (n = 15). There were no statistically significant differences between the groups in terms of the diameters. In group 1, no instrumentation or obturation was performed. The rest of the roots were chemomechanically prepared with nickel-titanium ProTaper rotary instruments up to size F3 at the working length. Group 2 was left unobturated. Groups 3 and 4 were obturated with AH Plus used with the matched-taper single-cone and lateral condensation techniques, respectively. In groups 5 and 6, MetaSEAL was used instead of AH Plus. All of the roots were mounted vertically in self-curing acrylic resin blocks that exposed 8 mm of the coronal part. Then the roots were subjected to a vertical loading force (1 mm/min). The force required to produce a fracture was recorded in newtons. The data were analyzed by using Kruskal-Wallis and post hoc Dunn multiple comparison tests (P < .05).
  
  
  RESULTS
  Although we did not detect statistical significance, there was a substantial difference between the fracture resistance values of the intact and instrumented but not obturated roots. The groups in which AH Plus and MetaSEAL were used with the matched-taper single-cone technique showed significantly higher fracture resistance values than the instrumented but not obturated roots (P < .05). There were no significant differences between the groups submitted to the matched-taper single-cone technique. The force required to fracture the roots in the group treated with AH Plus and the lateral condensation technique was similar to that required to fracture intact roots, whereas the group treated with MetaSEAL and the lateral condensation technique revealed comparable values to the instrumented but not obturated roots.
  
  
  CONCLUSIONS
  When used with the matched-taper single-cone technique, MetaSEAL and AH Plus have the potential to reinforce endodontically treated teeth.
authors.affiliation: Department of Endodontics, Faculty of Dentistry, İstanbul University, İstanbul, Turkey. ersev@istanbul.edu.tr
authors.forename: Handan
authors.initials: H
authors.lastname: Ersev
authors.forename: Bülent
authors.initials: B
authors.lastname: Yilmaz
authors.forename: Erdal
authors.initials: E
authors.lastname: Pehlivanoğlu
authors.forename: Ece
authors.initials: E
authors.lastname: Ozcan-Çalişkan
authors.forename: Fehmi Raif
authors.initials: FR
authors.lastname: Erişen
mesh_terms: D001641:Bicuspid; D003799:Dental Stress Analysis / Q000295:instrumentation; D004492:Edetic Acid / Q000627:therapeutic use; D004853:Epoxy Resins / Q000627:therapeutic use; D006171:Gutta-Percha / Q000627:therapeutic use; D006801:Humans; D006813:Humidity; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry / Q000627:therapeutic use*; D012387:Root Canal Filling Materials / Q000737:chemistry / Q000627:therapeutic use*; D012388:Root Canal Irrigants / Q000627:therapeutic use; D012389:Root Canal Obturation / Q000379:methods*; D018915:Root Canal Preparation / Q000295:instrumentation / Q000379:methods; D012973:Sodium Hypochlorite / Q000627:therapeutic use; D013314:Stress, Mechanical; D013696:Temperature; D013997:Time Factors; D014082:Tooth Fractures / Q000503:physiopathology*; D014092:Tooth Root / Q000503:physiopathology*; D019553:Tooth, Nonvital / Q000503:physiopathology / Q000628:therapy*
chemical_list: D004853:Epoxy Resins; D008689:Methacrylates; D012387:Root Canal Filling Materials; D012388:Root Canal Irrigants; C534916:epoxy resin-based root canal sealer; C534239:metaseal; D006171:Gutta-Percha; D004492:Edetic Acid; D012973:Sodium Hypochlorite