title: Fatigue failure of dentin-composite disks subjected to cyclic diametral compression.
abstract: OBJECTIVE
  Our aim was to establish the relationship between cyclic loading and fatigue life of the dentin-composite interface using the newly developed disk in diametral compression tests. The results were then used to estimate the fatigue life of restored teeth under occlusal loading.
  
  
  METHODS
  Disk specimens (5mm dia.×2mm thick) were prepared using bovine incisors and restored with either a methacrylate-based composite Z100™ with Adper Single Bond Plus (Z100) or silorane-based composite Filtek™ LS with LS System adhesive (LS). The dentin-composite disks were tested under cyclic diametral compression to determine the number of cycles to failure (Nf) at three load levels (n=3 per group). Finite element analysis (FEA) was used to calculate the interfacial stresses (σ) within the specimen, to establish the σ vs. Nf curves, and those within a restored tooth under normal chewing forces (15N maximum). These were then used to estimate the lifetime of the restored tooth for the two restorative systems.
  
  
  RESULTS
  The disks restored with LS had a higher fatigue resistance than those restored with Z100. The maximum interfacial stress in the restored tooth determined by FEA was ∼0.5MPa. Based on the estimate of 300,000 cycles of chewing per year, the predicted lifetime under occlusal loading for teeth restored with LS and Z100 was 33 and 10 years, respectively.
  
  
  CONCLUSIONS
  The disk in cyclic diametral compression has been used successfully to provide fatigue data which allows the lifetime of composite-restored teeth under occlusal loading to be predicted using numerical simulation.
authors.affiliation: Minnesota Dental Research Center for Biomaterials and Biomechanics (MDRCBB), School of Dentistry, University of Minnesota, MN, USA.
authors.forename: Yuping
authors.initials: Y
authors.lastname: Li
authors.affiliation: Minnesota Dental Research Center for Biomaterials and Biomechanics (MDRCBB), School of Dentistry, University of Minnesota, MN, USA; Department of Diagnostic and Biological Sciences, School of Dentistry, University of Minnesota, MN, USA.
authors.forename: Carola
authors.initials: C
authors.lastname: Carrera
authors.affiliation: Department of Diagnostic and Biological Sciences, School of Dentistry, University of Minnesota, MN, USA.
authors.forename: Ruoqiong
authors.initials: R
authors.lastname: Chen
authors.affiliation: Minnesota Dental Research Center for Biomaterials and Biomechanics (MDRCBB), School of Dentistry, University of Minnesota, MN, USA.
authors.forename: Jianying
authors.initials: J
authors.lastname: Li
authors.affiliation: Minnesota Dental Research Center for Biomaterials and Biomechanics (MDRCBB), School of Dentistry, University of Minnesota, MN, USA.
authors.forename: Yungchung
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Department of Diagnostic and Biological Sciences, School of Dentistry, University of Minnesota, MN, USA.
authors.forename: Patricia
authors.initials: P
authors.lastname: Lenton
authors.affiliation: Department of Diagnostic and Biological Sciences, School of Dentistry, University of Minnesota, MN, USA.
authors.forename: Joel D
authors.initials: JD
authors.lastname: Rudney
authors.affiliation: Department of Developmental and Surgical Sciences, School of Dentistry, University of Minnesota, MN, USA.
authors.forename: Robert S
authors.initials: RS
authors.lastname: Jones
authors.affiliation: Minnesota Dental Research Center for Biomaterials and Biomechanics (MDRCBB), School of Dentistry, University of Minnesota, MN, USA.
authors.forename: Conrado
authors.initials: C
authors.lastname: Aparicio
authors.affiliation: Minnesota Dental Research Center for Biomaterials and Biomechanics (MDRCBB), School of Dentistry, University of Minnesota, MN, USA. Electronic address: alexfok@umn.edu.
authors.forename: Alex
authors.initials: A
authors.lastname: Fok
mesh_terms: D000818:Animals; D002417:Cattle; D003188:Composite Resins / Q000737:chemistry*; D003738:Dental Cements / Q000737:chemistry; D019232:Dental Restoration Failure; D003793:Dental Restoration, Permanent; D003799:Dental Stress Analysis; D003804:Dentin / Q000737:chemistry*; D020342:Finite Element Analysis; D066298:In Vitro Techniques; D007180:Incisor; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D011312:Pressure; D013718:Tensile Strength
chemical_list: C554641:Adper single bond 2; D003188:Composite Resins; D003738:Dental Cements; C543062:Filtek LS Low Shrink resin
keywords: Composite resin; Dental restorations; Diametral compression; Fatigue lifetime; Finite element analysis; Interfacial integrity