title: Evaluation of the attractive force of different types of new-generation magnetic attachment systems.
abstract: BACKGROUND
  Rare earth magnets have been used in prosthodontics, but their tendency for corrosion in the oral cavity and insufficient attractive forces limit long-term clinical application.
  
  
  OBJECTIVE
  The purpose of this study was to evaluate the attractive force of different types of new-generation magnetic attachment systems.
  
  
  METHODS
  The attractive force of the neodymium-iron-boron (Nd-Fe-B) and samarium-cobalt (Sm-Co) magnetic attachment systems, including closed-field (Hilop and Hicorex) and open-field (Dyna and Steco) systems, was measured in a universal testing machine (n=5). The data were statistically evaluated with 1-way ANOVA and post hoc Tukey-Kramer multiple comparison test (α=.05).
  
  
  RESULTS
  The closed-field systems exhibited greater (P<.001) attractive force than the open-field systems. Moreover, there was a statistically significant difference in attractive force between Nd-Fe-B and Sm-Co magnets (P<.001). The strongest attractive force was found with the Hilop system (9.2 N), and the lowest force was found with the Steco system (2.3 N).
  
  
  CONCLUSIONS
  The new generation of Nd-Fe-B closed-field magnets, along with improved technology, provides sufficient denture retention for clinical application.
authors.affiliation: Department of Prosthodontics, University of Cumhuriyet, Faculty of Dentistry, Sivas, Turkey. dthkn@hotmail.com
authors.forename: Hakan
authors.initials: H
authors.lastname: Akin
authors.forename: M Emre
authors.initials: ME
authors.lastname: Coskun
authors.forename: E Gulsah
authors.initials: EG
authors.lastname: Akin
authors.forename: A Kemal
authors.initials: AK
authors.lastname: Ozdemir
mesh_terms: D001895:Boron / Q000737:chemistry; D003035:Cobalt / Q000737:chemistry; D003799:Dental Stress Analysis / Q000295:instrumentation; D003781:Denture Retention / Q000295:instrumentation*; D006801:Humans; D007501:Iron / Q000737:chemistry; D008280:Magnetics / Q000295:instrumentation*; D008674:Metals, Rare Earth / Q000737:chemistry; D009354:Neodymium / Q000737:chemistry; D012493:Samarium / Q000737:chemistry
chemical_list: D008674:Metals, Rare Earth; D009354:Neodymium; D003035:Cobalt; D012493:Samarium; D007501:Iron; D001895:Boron