title: Surface hardness and wear of glass ionomers and compomers.
abstract: OBJECTIVE
  To determine the surface hardness and in vitro wear of glass ionomer cements (GIC) and compomers in comparison with a resin composite and to test for a possible correlation between the determined hardness and wear values.
  
  
  METHODS
  Samples were made of conventional GIC (Ketac-Fil, Fuji II, Fuji IX, Ketac-Prototype = Ketac-Molar), resin-modified GIC (Photac-Fil, Fuji II LC, Vitremer), compomers (Dyract, Compoglass) and resin composite (Z100) for the hardness test (n = 10) and for the wear test (n = 3). The materials were handled according to the manufacturers' instructions. The samples were stored in deionized water for 48 hours at 37 degrees C prior to the determination of Rockwell hardness and three-body in vitro wear.
  
  
  RESULTS
  Hardness could not be measured on Ketac-Fil and Fuji II as the samples fractured before a reading was obtainable. Statistically significant differences were found in hardness and wear between brands and between the four types of material. Surface hardness: resin-modified GIC < conventional GIC = compomers < resin composite. In vitro wear: resin-modified GIC > compomers > conventional GIC > resin composite. A negative correlation between hardness and wear was recorded.
authors.affiliation: Department of Dental Materials, School of Dentistry, University of Copenhagen, Denmark.
authors.forename: A
authors.initials: A
authors.lastname: Peutzfeldt
authors.forename: F
authors.initials: F
authors.lastname: García-Godoy
authors.forename: E
authors.initials: E
authors.lastname: Asmussen
mesh_terms: D000704:Analysis of Variance; D020770:Compomers; D003188:Composite Resins / Q000737:chemistry*; D019554:Dental Restoration Wear; D005899:Glass Ionomer Cements / Q000737:chemistry*; D006244:Hardness; D016014:Linear Models; D008298:Maleates / Q000737:chemistry; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry*; D012117:Resins, Synthetic / Q000737:chemistry; D017640:Silicates / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D013499:Surface Properties; D015040:Zirconium / Q000737:chemistry
chemical_list: C105428:Compoglass; D020770:Compomers; D003188:Composite Resins; C088486:Dyract; C079765:Fuji II LC cement; D005899:Glass Ionomer Cements; D008298:Maleates; D008689:Methacrylates; C081144:Photac-Fil; D019279:Resin Cements; D012117:Resins, Synthetic; D017640:Silicates; C084550:Vitremer; C083568:Z100 composite resin; C110713:fuji IX; C110712:ketac-molar; C084541:Fuji glass-ionomer lining cement; D012822:Silicon Dioxide; C040964:Ketac-Fil; D015040:Zirconium