title: Fracture load of CAD/CAM-generated slot-inlay FPDs.
abstract: OBJECTIVE
  This study investigated fracture load of computer-aided design/manufacturing (CAD/CAM)-generated slot-inlay fixed partial dentures (FPD) machined from ceramic and composite.
  
  
  METHODS
  Ninety slot-inlay FPDs were machined in groups of 15 specimens each using the same design on a Cerec 3 unit. Materials were assigned to groups: (1) Mk II feldspathic ceramic, (2) ProCAD glass-ceramic, (3) glass-ceramic 1, (4) glass-ceramic 2, (5) composite 1, and (6) composite 2. The slot-inlay FPDs were placed on models with two abutment teeth without cementation and loaded to fracture. For control, test bars (n = 15) were machined from each of the materials, and flexural strength was examined using three-point bending. Data were statistically analyzed using ANOVA and Scheffé tests.
  
  
  RESULTS
  Fracture load of groups 4 (1,557 N, SD 236), 5 (1,048 N, SD 77), and 6 (1,512 N, SD 106) was significantly higher than that of groups 1 (652 N, SD 53) and 2 (773 N, SD 65). Flexural strength of group 4 (256 MPa, SD 20) was significantly higher than that of groups 1 (103 MPa, SD 6), 2 (127 MPa, SD 15), 3 (162 MPa, SD 32), 5 (178 MPa, SD 18), and 6 (170 MPa, SD 20).
  
  
  CONCLUSIONS
  Fracture loads of glass-ceramic 2 and composite 2 appear adequate for CAD/CAM slot-inlay FPDs.
authors.affiliation: Clinic of the Division of Aesthetics and Computer Restorations, Department of Preventive Dentistry, Periodontology and Cariology, Center for Dental and Oral Medicine, University of Zurich, Switzerland.
authors.forename: Andreas
authors.initials: A
authors.lastname: Bindl
authors.forename: Heinz
authors.initials: H
authors.lastname: Lüthy
authors.forename: Werner H
authors.initials: WH
authors.lastname: Mörmann
mesh_terms: D000538:Aluminum Silicates / Q000737:chemistry; D000704:Analysis of Variance; D002516:Ceramics / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry; D017076:Computer-Aided Design; D000044:Dental Abutments; D003776:Dental Porcelain / Q000737:chemistry; D019232:Dental Restoration Failure; D003779:Denture Design; D003830:Denture, Partial, Fixed; D005898:Glass / Q000737:chemistry; D006801:Humans; D007284:Inlays; D008422:Materials Testing; D018583:Pliability; D017680:Potassium Compounds / Q000737:chemistry; D013314:Stress, Mechanical; D016474:Weight-Bearing
chemical_list: D000538:Aluminum Silicates; D003188:Composite Resins; D017680:Potassium Compounds; C454801:ProCAD Ceramic; D003776:Dental Porcelain; C016447:feldspar; C074543:Cerec