title: Interface gap size of manually and CAD/CAM-manufactured ceramic inlays/onlays in vitro.
abstract: OBJECTIVE
  To determine the fit of ceramic inlays manufactured using a recently introduced CAD/CAM-system (Decim) and of two types of laboratory-made heat-pressed ceramics (IPS Empress and Opc).
  
  
  METHODS
  Extracted human premolars were prepared to receive mesio-occlusodistal (MOD) ceramic inlays, for which 10 Denzir, 10 IPS Empress, and 10 Opc were fabricated. The Denzir restorations were produced by the manufacturer of the CAD/CAM-system, and the IPS Empress and Opc by student dental technicians. Before luting the internal fit on the diestone models and on the premolars was determined using replicas. After luting on the premolars with a resin composite the marginal and internal fit were measured. The values were analyzed statistically using ANOVA and Scheffe's test at a significance level of p<0.05.
  
  
  RESULTS
  Before luting there were no significant differences (p>0.05) in the internal gap width between the three systems studied when placed on their matching diestone models. When placed on the premolars a significant difference (p<0.01) in the internal fit was seen between Empress and Opc before luting, whereas there were no significant differences (p>0.05) between Empress and Denzir and between Opc and Denzir. Between the diestone models and the premolars there were significant differences (p<0.01) in the internal fit, except for IPS Empress. After luting there were no significant differences (p>0.05) between IPS Empress and Denzir, whereas the marginal gap width was significantly wider (p<0.001) for Opc than for IPS Empress and Denzir. The internal fit was significantly (p<0.001) wider for Opc than for IPS Empress, whereas there were no significant differences (p>0.05) between IPS Empress and Denzir or between Opc and Denzir.
  
  
  CONCLUSIONS
  After luting there were only slight differences in the fit between the restorations fabricated using the three different manufacturing techniques and ceramics. Therefore, long-term follow-up studies are needed to assess the clinical significance of the slight differences between the three systems.
authors.affiliation: Department of Dental Materials Science, Faculty of Medicine and Odontology, Umeå University, SE-901 87 Umeå, Sweden.
authors.forename: Simon
authors.initials: S
authors.lastname: Addi
authors.forename: Arjang
authors.initials: A
authors.lastname: Hedayati-Khams
authors.forename: Amin
authors.initials: A
authors.lastname: Poya
authors.forename: Göran
authors.initials: G
authors.lastname: Sjögren
mesh_terms: D000538:Aluminum Silicates; D001641:Bicuspid; D002484:Cementation; D017076:Computer-Aided Design; D018772:Dental Marginal Adaptation; D003776:Dental Porcelain; D006801:Humans; D007284:Inlays; D019279:Resin Cements; D013674:Technology, Dental / Q000379:methods
chemical_list: D000538:Aluminum Silicates; C453860:Denzir; C075815:IPS-Empress ceramic; C105911:Optimal Pressed Ceramic; C438843:Panavia-Fluoro; D019279:Resin Cements; D003776:Dental Porcelain