title: Wear and mechanical properties of nano-silica-fused whisker composites.
abstract: Resin composites must be improved if they are to overcome the high failure rates in large stress-bearing posterior restorations. This study aimed to improve wear resistance via nano-silica-fused whiskers. It was hypothesized that nano-silica-fused whiskers would significantly improve composite mechanical properties and wear resistance. Nano-silicas were fused onto whiskers and incorporated into a resin at mass fractions of 0%-74%. Fracture toughness (mean +/- SD; n = 6) was 2.92 +/- 0.14 MPa.m(1/2) for whisker composite with 74% fillers, higher than 1.13 +/- 0.19 MPa.m(1/2) for a prosthetic control, and 0.95 +/- 0.11 MPa.m(1/2) for an inlay/onlay control (Tukey's at 0.95). A whisker composite with 74% fillers had a wear depth of 77.7 +/- 6.9 mum, less than 118.0 +/- 23.8 microm of an inlay/onlay control, and 172.5 +/- 15.4 microm of a prosthetic control (p < 0.05). Linear correlations were established between wear and hardness, modulus, strength, and toughness, with R = 0.95-0.97. Novel nano-silica-fused whisker composites possessed high toughness and wear resistance with smooth worn surfaces, and may be useful in large stress-bearing restorations.
authors.affiliation: Paffenbarger Research Center, American Dental Association Foundation, National Institute of Standards and Technology, Building 224, Room A-153, Stop 8546, Gaithersburg, MD 20899-8546, USA. hockin.xu@nist.gov
authors.forename: H H K
authors.initials: HH
authors.lastname: Xu
authors.forename: J B
authors.initials: JB
authors.lastname: Quinn
authors.forename: A A
authors.initials: AA
authors.lastname: Giuseppetti
mesh_terms: D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D019554:Dental Restoration Wear; D004548:Elasticity; D005899:Glass Ionomer Cements / Q000737:chemistry; D006244:Hardness; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D049329:Nanostructures / Q000737:chemistry*; D010316:Particle Size; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D019904:Polymethyl Methacrylate / Q000737:chemistry; D011140:Polyurethanes / Q000737:chemistry; D012821:Silanes / Q000737:chemistry; D012823:Silicate Cement / Q000737:chemistry; D017655:Silicon Compounds / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*; D013314:Stress, Mechanical; D013499:Surface Properties
chemical_list: D003188:Composite Resins; D005899:Glass Ionomer Cements; D008689:Methacrylates; D011109:Polymethacrylic Acids; D011140:Polyurethanes; D012821:Silanes; D017655:Silicon Compounds; C111282:dental polyglass; C029824:urethane dimethacrylate luting resin; D012823:Silicate Cement; C020946:triethylene glycol dimethacrylate; C017492:methacryloxypropyltrimethoxysilane; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate; D012822:Silicon Dioxide; D019904:Polymethyl Methacrylate; C032734:silicon nitride