title: Flexural properties of experimental nanofiber reinforced composite are affected by resin composition and nanofiber/resin ratio.
abstract: OBJECTIVE
  To evaluate the influence of different resin blends concentrations and nanofibers mass ratio on flexural properties of experimental Poliacrylonitrile (PAN) nanofibers reinforced composites.
  
  
  METHODS
  Poliacrylonitrile (PAN) nanofibers mats were produced by electrospinning and characterized by tensile testing and scanning electron microscopy (SEM). Experimental resin-fiber composite beams were manufactured by infiltrating PAN nanofiber mats with varied concentrations of BisGMA-TEGDMA resin blends (BisGMA/TEGDMA: 30/70, 50/50 and 70/30weight%). The mass ratio of fiber to resin varied from 0% to 8%. Beams were cured and stored in water at 37°C. Flexural strength (FS), flexural modulus (FM) and work of fracture (WF) were evaluated by three-point bending test after 24h storage.
  
  
  RESULTS
  The tensile properties of the PAN nanofibers indicated an anisotropic behavior being always higher when tested in a direction perpendicular to the rotation of the collector drum. Except for WF, the other flexural properties (FS and FM) were always higher as the ratio of BisGMA to TEGDMA increased in the neat resin beams. The addition of different ratios of PAN fibers did not affect FS and FM of the composite beams as compared to neat resin beams (p>0.05). However, the addition of fibers significantly increased the WF of the composite beams, and this was more evident for the blends with higher TEGDMA ratios (p<0.05).
  
  
  CONCLUSIONS
  The inclusion of PAN nanofibers into resin blends did not negatively affect the properties of the composite and resulted in an increase in toughness that is a desirable property for a candidate material for prosthodontics application.
authors.affiliation: Department of Prosthodontics, Bauru School of Dentistry, University of São Paulo, Al. Octávio Pinheiro Brisola, 9-75, Bauru, SP, 17012-901, Brazil. Electronic address: hvidotti@yahoo.com.br.
authors.forename: Hugo A
authors.initials: HA
authors.lastname: Vidotti
authors.affiliation: Department of Oral Biological and Medical Sciences, Division of Biomaterials, The University of British Columbia, Faculty of Dentistry, 368-2199 Wesbrook Mall, Vancouver, BC, V6T 1Z3, Canada. Electronic address: amanso@dentistry.ubc.ca.
authors.forename: Adriana P
authors.initials: AP
authors.lastname: Manso
authors.affiliation: Department of Materials Engineering, The University of British Columbia, Faculty of Applied Sciences, 309-6350 Stores Road, Vancouver, BC, V6T 1Z4, Canada. Electronic address: victorkaleung@gmail.com.
authors.forename: Victor
authors.initials: V
authors.lastname: Leung
authors.affiliation: Department of Prosthodontics, Bauru School of Dentistry, University of São Paulo, Al. Octávio Pinheiro Brisola, 9-75, Bauru, SP, 17012-901, Brazil. Electronic address: accaciodovalle@yahoo.com.br.
authors.forename: Accácio L
authors.initials: AL
authors.lastname: do Valle
authors.affiliation: Department of Materials Engineering, The University of British Columbia, Faculty of Applied Sciences, 309-6350 Stores Road, Vancouver, BC, V6T 1Z4, Canada. Electronic address: frank.ko@ubc.ca.
authors.forename: Frank
authors.initials: F
authors.lastname: Ko
authors.affiliation: Department of Oral Biological and Medical Sciences, Division of Biomaterials, The University of British Columbia, Faculty of Dentistry, 368-2199 Wesbrook Mall, Vancouver, BC, V6T 1Z3, Canada. Electronic address: rickmc@dentistry.ubc.ca.
authors.forename: Ricardo M
authors.initials: RM
authors.lastname: Carvalho
mesh_terms: D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D003793:Dental Restoration, Permanent; D003799:Dental Stress Analysis; D004548:Elasticity; D006801:Humans; D008855:Microscopy, Electron, Scanning; D057139:Nanofibers / Q000737:chemistry*; D018583:Pliability; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D013499:Surface Properties; D013718:Tensile Strength
chemical_list: D003188:Composite Resins; D011109:Polymethacrylic Acids; C020946:triethylene glycol dimethacrylate; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate
keywords: Electrospinning; Flexural properties; Nanofibers; Polyacrylonitrile; Resin composite