title: Contact- and contact-free wear between various resin composites.
abstract: OBJECTIVE
  Nowadays direct and indirect resin composites are frequently applied to build up the occlusion when extensive tooth wear took place. To achieve long-lasting restorations it is essential to obtain knowledge about their interactions due to occlusal contacts. Therefore, the two- and three-body wear between frequently used direct and indirect resin composites was investigated.
  
  
  METHODS
  The two- and three-body wear of three direct resin composites and three indirect resin composites, with Clearfil AP-X, Filtek Z250, and Filtek Supreme XT as antagonists, were measured, using the ACTA wear device. The wear rates were determined and the surfaces were evaluated with SEM.
  
  
  RESULTS
  The most remarkable outcome was that the two-body wear rate of the different composites opposing the Z250 wheel were significantly higher. Furthermore, it was shown that the three-body wear rate was independent on the antagonist and in general higher than the two-body wear rate.
  
  
  CONCLUSIONS
  To reduce abrasion of the opposing resin composite surface the resin composite fillers should consist of a softer glass, e.g. barium glass or in case of a harder filler the size should be reduced to nano-size.
authors.affiliation: Department of Integrated Dentistry, Jagiellonian University, Krakow, Poland; Department of Dental Materials Science, Academic Centre for Dentistry Amsterdam (ACTA), Universiteit van Amsterdam and Vrije Universiteit, Amsterdam, The Netherlands.
authors.forename: Magdalena A
authors.initials: MA
authors.lastname: Osiewicz
authors.affiliation: Department of Dental Materials Science, Academic Centre for Dentistry Amsterdam (ACTA), Universiteit van Amsterdam and Vrije Universiteit, Amsterdam, The Netherlands.
authors.forename: Arie
authors.initials: A
authors.lastname: Werner
authors.affiliation: Department of Integrated Dentistry, Jagiellonian University, Krakow, Poland.
authors.forename: Jolanta
authors.initials: J
authors.lastname: Pytko-Polonczyk
authors.affiliation: Department of Dental Materials Science, Academic Centre for Dentistry Amsterdam (ACTA), Universiteit van Amsterdam and Vrije Universiteit, Amsterdam, The Netherlands.
authors.forename: Franciscus J M
authors.initials: FJ
authors.lastname: Roeters
authors.affiliation: Department of Dental Materials Science, Academic Centre for Dentistry Amsterdam (ACTA), Universiteit van Amsterdam and Vrije Universiteit, Amsterdam, The Netherlands. Electronic address: c.kleverlaan@acta.nl.
authors.forename: Cornelis J
authors.initials: CJ
authors.lastname: Kleverlaan
mesh_terms: D003188:Composite Resins / Q000737:chemistry*; D019554:Dental Restoration Wear; D006244:Hardness; D066298:In Vitro Techniques; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D013499:Surface Properties
chemical_list: C112828:Clearfil AP-X; D003188:Composite Resins; C474035:Filtek Supreme; C444701:Filtek Z250; D008689:Methacrylates
keywords: Resin composite; Tooth wear; Wear