title: In-vivo evaluation of a feldspathic ceramic system: 2-year results.
abstract: OBJECTIVE
  The aim of this clinical study was to evaluate feldspathic ceramic inlays by clinical criteria and quantitative margin analysis, and to compare clinical performance with the quantitative margin analysis results.
  
  
  METHODS
  Fifty fibre-reinforced feldspathic ceramic inlays were placed in box-shaped, Class II preparations with all margins located in enamel. A low-viscosity type dual-curing resin luting material was used for luting. The inlays were evaluated clinically according to modified US Public Health Service criteria after 2 days, 1 year, and 2 years. In addition, quantitative margin analysis was performed under a scanning electron microscope using an image analysing system.
  
  
  RESULTS
  Clinically the inlays performed very well after 2 years, showing no changes in colour, no recurrent caries and no marginal discolouration. Because of the wear of the composite resin luting material, margins were perceptible with an explorer in 54% of the cases after 2 years. Quantitative margin analysis showed significantly (P < or = 0.05) more marginal gaps at the composite/ceramic interface compared with the enamel/composite interface at each evaluation. There was a significant increase in marginal gaps at both interfaces during the first year, whereas marginal gaps at the composite/ceramic interface did not increase significantly during the second year. Quantitative margin analysis showed that both time and interface had a significant influence on marginal gaps.
  
  
  CONCLUSIONS
  Quantitative margin analysis should be included in clinical long-term trials on this type of restoration to recognize possible deficiencies in ceramic, composite resin luting material, and the luting interfaces.
authors.affiliation: Department of Operative Dentistry and Periodontology, Dental School, University of Regensburg, Germany.
authors.forename: K H
authors.initials: KH
authors.lastname: Friedl
authors.forename: G
authors.initials: G
authors.lastname: Schmalz
authors.forename: K A
authors.initials: KA
authors.lastname: Hiller
authors.forename: A
authors.initials: A
authors.lastname: Saller
mesh_terms: D000328:Adult; D000538:Aluminum Silicates / Q000737:chemistry; D002484:Cementation; D002516:Ceramics / Q000737:chemistry; D002986:Clinical Trials as Topic; D003116:Color; D003188:Composite Resins / Q000737:chemistry; D003731:Dental Caries / Q000209:etiology; D003737:Dental Cavity Preparation / Q000145:classification; D003738:Dental Cements / Q000737:chemistry; D003743:Dental Enamel / Q000648:ultrastructure; D018772:Dental Marginal Adaptation; D005069:Evaluation Studies as Topic; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007284:Inlays; D008297:Male; D008855:Microscopy, Electron, Scanning; D008875:Middle Aged; D017680:Potassium Compounds / Q000737:chemistry; D012008:Recurrence; D013499:Surface Properties; D014783:Viscosity
chemical_list: D000538:Aluminum Silicates; D003188:Composite Resins; D003738:Dental Cements; D017680:Potassium Compounds; C016447:feldspar