title: Eight-year randomized clinical evaluation of Class II nanohybrid resin composite restorations bonded with a one-step self-etch or a two-step etch-and-rinse adhesive.
abstract: OBJECTIVE
  The aim of this study is to observe the durability of Class II nanohybrid resin composite restorations, placed with two different adhesive systems, in an 8-year follow-up.
  
  
  METHODS
  Seventy-eight participants received at random at least two Class II restorations of the ormocer-based nanohybrid resin composite (Ceram X) bonded with either a one-step self-etch adhesive (Xeno III) or a control two-step etch-and-rinse adhesive (Excite). The 165 restorations were evaluated using slightly modified United States Public Health Services (USPHS) criteria at baseline and then yearly during 8 years.
  
  
  RESULTS
  One hundred and fifty-eight restorations were evaluated after 8 years. Three participants with five restorations (three Xeno III, two Excite) were registered as dropouts. Twenty-one failed restorations (13.3%) were observed during the follow-up. Twelve in the one-step self-etch adhesive group (13.5%) and nine in the two-step etch-and-rinse group (13.0%). This resulted in nonsignificant different annual failure rates of 1.69 and 1.63%, respectively. Fracture of restoration was the main reason for failure.
  
  
  CONCLUSIONS
  Good clinical performance was shown during the 8-year evaluation and no significant difference in overall clinical performance between the two adhesives. Fracture was the main reason for failure.
  
  
  CONCLUSIONS
  The one-step self-etch adhesive showed a good long-term clinical effectiveness in combination with the nanohybrid resin composite in Class II restorations.
authors.affiliation: Department of Odontology, Dental School Umeå, Faculty of Medicine, Umeå University, SE-901 87, Umeå, Sweden, Jan.van.Dijken@odont.umu.se.
authors.forename: Jan W V
authors.initials: JW
authors.lastname: van Dijken
authors.forename: Ulla
authors.initials: U
authors.lastname: Pallesen
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003188:Composite Resins / Q000737:chemistry*; D003718:Denmark; D001840:Dental Bonding / Q000379:methods*; D019232:Dental Restoration Failure; D003793:Dental Restoration, Permanent / Q000379:methods*; D017220:Dentin-Bonding Agents; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008689:Methacrylates; D008875:Middle Aged; D049329:Nanostructures / Q000737:chemistry
chemical_list: C520091:CeramX; D003188:Composite Resins; D017220:Dentin-Bonding Agents; C420130:Excite cement; D008689:Methacrylates; C487957:Xeno III