title: The effect of a leucite-containing ceramic filler on the abrasive wear of dental composites.
abstract: OBJECTIVE
  The aim of this study was to evaluate abrasive wear of a dental composite based on a leucite-containing (KAlSi2O2 ceramic filler, and to compare it with the wear of a composite based on commonly used aluminum barium silicate glass filler.
  
  
  METHODS
  IPS Empress (Ivoclar-Vivadent) ingots were ball milled, passed through an 800 mesh (ASTM) sieve, and used as the leucite ceramic filler. Experimental composites were prepared by mixing the silane-treated fillers with the resin monomers. The resin consisted of 70 wt% Bis-GMA and 30 wt% TEGDMA containing camphorquinone and DMAEMA as the photoinitiator system. Glass-based composites were also prepared using silane-treated aluminum barium silicate glass fillers and the same resin system. TetricCeram, a commercially available dental composite, was used as control. Spherical specimens of the composites were then prepared and kept in water for 2 weeks to reach equilibrium with water. An abrasive wear test was performed using a device designed in our laboratory and weight loss of the specimens was measured as an abrasion parameter after each 50 h. SEMs were taken from worn and fractured surfaces. Degree-of-conversion of the composites was measured using FTIR spectroscopy. Vickers surface microhardness, flexural strength, and flexural modulus of the composites were also measured. The data were analyzed and compared using ANOVA and Tukey HSD tests (significance level=0.05).
  
  
  RESULTS
  The results showed that there were significant differences among the abrasive wear of the composites (p<0.05). The ranking from least to most was as: leucite-based composite<TetricCeram<glass-based composite. The higher wear resistance of leucite-based composite could be related to its higher surface hardness.
  
  
  CONCLUSIONS
  Using leucite-containing glass as an alternative for aluminum barium silicate glass fillers in dental composites generated a significant increase in the wear resistance of the resin composites which should be beneficial in the development of dental materials.
authors.affiliation: Iran Polymer and Petrochemical Institute, P.O. Box 14965/115, Tehran, Iran. M.Atai@ippi.ac.ir
authors.forename: Mohammad
authors.initials: M
authors.lastname: Atai
authors.forename: Esmaeil
authors.initials: E
authors.lastname: Yassini
authors.forename: Maryam
authors.initials: M
authors.lastname: Amini
authors.forename: David C
authors.initials: DC
authors.lastname: Watts
mesh_terms: D000538:Aluminum Silicates / Q000737:chemistry*; D017609:Barium Compounds / Q000737:chemistry; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D002516:Ceramics / Q000737:chemistry*; D003188:Composite Resins / Q000737:chemistry*; D003764:Dental Materials / Q000737:chemistry*; D003776:Dental Porcelain / Q000737:chemistry; D019554:Dental Restoration Wear; D004548:Elasticity; D005898:Glass / Q000737:chemistry; D006244:Hardness; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D018583:Pliability; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D019163:Reducing Agents / Q000737:chemistry; D012821:Silanes / Q000737:chemistry; D017640:Silicates / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D013729:Terpenes / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D000538:Aluminum Silicates; D017609:Barium Compounds; D003188:Composite Resins; D003764:Dental Materials; C075815:IPS-Empress ceramic; D008689:Methacrylates; D011109:Polymethacrylic Acids; D019163:Reducing Agents; D012821:Silanes; D017640:Silicates; D013729:Terpenes; C121818:Tetric ceram; D014867:Water; D003776:Dental Porcelain; C078519:leucite; C020946:triethylene glycol dimethacrylate; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate; C048339:camphoroquinone; C049840:2-(dimethylamino)ethyl methacrylate