title: Colour stainability of indirect CAD-CAM processed composites vs. conventionally laboratory processed composites after immersion in staining solutions.
abstract: OBJECTIVE
  The aim of this study was to determine, by using a spectrophotometer device, the colour stainability of two indirect CAD/CAM processed composites in comparison with two conventionally laboratory-processed composites after being immersed 4 weeks in staining solutions such as coffee, black tea and red wine, using distilled water as control group.
  
  
  METHODS
  Two indirect CAD/CAM composites (Lava Ultimate and Paradigm MZ100) and two conventionally laboratory-processed composites (SR Adoro and Premise Indirect) of shade A2 were selected (160 disc samples). Colour stainability was measured after 4 weeks of immersion in three staining solutions (black tea, coffee, red wine) and distilled water. Specimen's colour was measured each week by means of a spectrophotometer (CIE L*a*b* system). Statistical analysis was carried out performing repeated ANOVA measurements and Tukey's HSD test to evaluate differences in ΔE00 measurements between groups; the interactions among composites, staining solutions and time duration were also evaluated.
  
  
  RESULTS
  All materials showed significant discoloration (p<0.01) when compared to control group. The highest ΔE00 observed was with red wine, whereas black tea showed the lowest one. Indirect laboratory-processed resin composites showed the highest colour stability compared with CAD/CAM resin blocks.
  
  
  CONCLUSIONS
  CAD/CAM processed composites immersed in staining solutions showed lower colour stability when compared to conventionally laboratory-processed resin composites.
  
  
  CONCLUSIONS
  The demand for CAD/CAM restorations has been increasing; however, colour stainability for such material has been insufficiently studied. Moreover, this has not been performed comparing CAD/CAM processed composites versus laboratory-processed indirect composites by immersing in staining solutions for long immersion periods.
authors.affiliation: Department of Restorative Dentistry and Endodontics, International University of Catalonia, Barcelona, Spain.
authors.forename: Mariana A
authors.initials: MA
authors.lastname: Arocha
authors.affiliation: Department of Restorative Dentistry and Endodontics, International University of Catalonia, Barcelona, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Basilio
authors.affiliation: Department of Biostatistics, International University of Catalonia, Barcelona, Spain.
authors.forename: Jaume
authors.initials: J
authors.lastname: Llopis
authors.affiliation: Departments of Economics and Quantitative Methods, University of Genoa, Italy.
authors.forename: Enrico
authors.initials: E
authors.lastname: Di Bella
authors.affiliation: Department of Restorative Dentistry and Endodontics, International University of Catalonia, Barcelona, Spain.
authors.forename: Miguel
authors.initials: M
authors.lastname: Roig
authors.affiliation: Division of Cariology and Endodontology, School of Dentistry, University of Geneva, Switzerland.
authors.forename: Stefano
authors.initials: S
authors.lastname: Ardu
authors.affiliation: Department of Restorative Dentistry and Endodontics, International University of Catalonia, Barcelona, Spain. Electronic address: juanrmayoral@uic.es.
authors.forename: Juan R
authors.initials: JR
authors.lastname: Mayoral
mesh_terms: D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003069:Coffee; D003116:Color; D004396:Coloring Agents / Q000737:chemistry*; D003188:Composite Resins / Q000737:chemistry*; D017076:Computer-Aided Design; D003764:Dental Materials / Q000737:chemistry*; D006801:Humans; D007101:Immersion; D007754:Laboratories, Dental; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D011140:Polyurethanes / Q000737:chemistry; D011897:Random Allocation; D013053:Spectrophotometry / Q000295:instrumentation; D013194:Staining and Labeling; D013499:Surface Properties; D013662:Tea; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000737:chemistry; D014920:Wine; D015040:Zirconium / Q000737:chemistry
chemical_list: D003069:Coffee; D004396:Coloring Agents; D003188:Composite Resins; D003764:Dental Materials; D008689:Methacrylates; D011109:Polymethacrylic Acids; D011140:Polyurethanes; D013662:Tea; C452079:paradigm MZ100; C507210:premise composite resin; D014867:Water; C029824:urethane dimethacrylate luting resin; C020946:triethylene glycol dimethacrylate; D011092:Polyethylene Glycols; C074277:ethoxylated bis-phenol A dimethacrylate; D017438:Bisphenol A-Glycidyl Methacrylate; D015040:Zirconium
keywords: CAD/CAM; Colour stability; Resin-composites; Stainability; Staining