title: Fracture resistance of endodontically-treated premolars adhesively restored.
abstract: OBJECTIVE
  To investigate the cusp fracture resistance of endodontically treated teeth, adhesively restored with various materials.
  
  
  METHODS
  MOD preparations and endodontic treatment was carried out on extracted sound maxillary premolars. The cavities were restored with the amalgam Valiant in combination with Superbond or Panavia bonding, the resin composites Z100, Herculite XRV or Clearfil RP with their respective bonding systems, Z100 in combination with the glass ionomers Ketac Fil, Fuji II and Vitremer, and Tetric in combination with Compoglass. Fracture resistance was measured by axial loading in an Instron testing machine.
  
  
  RESULTS
  One of the restorative methods, resin composites in combination with dentin bonding systems in beveled MOD preparations rendered the tooth a cusp fracture resistance which did not differ significantly from that of sound natural teeth. Two other restorative methods, bonded amalgam and a sandwich of glass ionomer cement/resin composite in beveled preparations were significantly weaker in resisting cusp fracture than sound natural teeth, but still significantly stronger than the unrestored tooth with a MOD preparation. It was statistically apparent that several adhesive restorative systems could satisfactorily be used to restore teeth after endodontic therapy.
authors.affiliation: Department of Endodontology and Cariology, School of Dentistry, University of Naples Federico II, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Ausiello
authors.forename: A J
authors.initials: AJ
authors.lastname: De Gee
authors.forename: S
authors.initials: S
authors.lastname: Rengo
authors.forename: C L
authors.initials: CL
authors.lastname: Davidson
mesh_terms: D000704:Analysis of Variance; D001641:Bicuspid / Q000503:physiopathology*; D003188:Composite Resins / Q000627:therapeutic use; D003723:Dental Amalgam / Q000627:therapeutic use; D003793:Dental Restoration, Permanent / Q000379:methods* / Q000706:statistics & numerical data; D017220:Dentin-Bonding Agents / Q000627:therapeutic use; D004198:Disease Susceptibility; D005899:Glass Ionomer Cements / Q000627:therapeutic use; D006801:Humans; D066298:In Vitro Techniques; D008437:Maxilla; D018709:Statistics, Nonparametric; D014082:Tooth Fractures / Q000209:etiology / Q000517:prevention & control*; D019553:Tooth, Nonvital / Q000150:complications / Q000628:therapy*
chemical_list: D003188:Composite Resins; D017220:Dentin-Bonding Agents; D005899:Glass Ionomer Cements; D003723:Dental Amalgam