title: Degree of conversion and bond strength of resin-cements to feldspathic ceramic using different curing modes.
abstract: OBJECTIVE
  The aim of this study was to assess the performance of resin cements when different curing modes are used, by evaluating the degree of conversion and bond strength to a ceramic substrate.
  
  
  METHODS
  Three resin cements were evaluated, two dual-cured (Variolink II and RelyX ARC) and one light-cured (Variolink Veneer). The dual-cured resin cements were tested by using the dual activation mode (base and catalyst) and light-activation mode (base paste only). For degree of conversion (DC) (n=5), a 1.0 mm thick feldspathic ceramic disc was placed over the resin cement specimens and the set was light activated with a QTH unit. After 24 h storage, the DC was measured with Fourier transform infrared spectroscopy (FTIR). For microshear bond strength testing, five feldspathic ceramic discs were submitted to surface treatment, and three cylindrical resin cement specimens were bonded to each ceramic surface according to the experimental groups. After 24 h, microshear bond testing was performed at 0.5 mm/min crosshead speed until the failure. Data were submitted to one-way ANOVA followed by Tukey test (p<0.05). Scanning electron microscopy (SEM) was used for classifying the failure modes.
  
  
  RESULTS
  Higher DC and bond strength values were shown by the resin cements cured by using the dual activation mode. The Variolink II group presented higher DC and bond strength values when using light-activation only when compared with the Variolink Veneer group.
  
  
  CONCLUSIONS
  The base paste of dual-cured resin cements in light-activation mode can be used for bonding translucent ceramic restorations of up to or less than 1.0 mm thick.
authors.affiliation: Universidade Federal de Uberlândia, Faculdade de Odontologia, Departamento de Dentística e Materiais Odontológicos, Uberlândia, MG, Brasil.
authors.forename: Veridiana Resende
authors.initials: VR
authors.lastname: Novais
authors.affiliation: Universidade Federal de Uberlândia, Faculdade de Odontologia, Departamento de Oclusão, Prótese Fixa e Materiais Odontológicos, Uberlândia, MG, Brasil.
authors.forename: Luís Henrique Araújo
authors.initials: LH
authors.lastname: Raposo
authors.affiliation: Universidade Federal de Uberlândia, Faculdade de Odontologia, Uberlândia, MG, Brasil.
authors.forename: Rafael Resende de
authors.initials: RR
authors.lastname: Miranda
authors.affiliation: Universidade Federal de Uberlândia, Faculdade de Odontologia, Uberlândia, MG, Brasil.
authors.forename: Camila de Carvalho Almança
authors.initials: CC
authors.lastname: Lopes
authors.affiliation: Universidade Federal de Uberlândia, Faculdade de Odontologia, Departamento de Oclusão, Prótese Fixa e Materiais Odontológicos, Uberlândia, MG, Brasil.
authors.forename: Paulo Cézar
authors.initials: PC
authors.lastname: Simamoto
authors.affiliation: Universidade Federal de Uberlândia, Faculdade de Odontologia, Departamento de Dentística e Materiais Odontológicos, Uberlândia, MG, Brasil.
authors.forename: Carlos José
authors.initials: CJ
authors.lastname: Soares
mesh_terms: D000538:Aluminum Silicates / Q000737:chemistry*; D000704:Analysis of Variance; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry*; D002516:Ceramics / Q000737:chemistry*; D055117:Curing Lights, Dental; D055115:Light-Curing of Dental Adhesives / Q000379:methods*; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D055668:Photochemical Processes; D011092:Polyethylene Glycols / Q000737:chemistry*; D058105:Polymerization; D011109:Polymethacrylic Acids / Q000737:chemistry*; D017680:Potassium Compounds / Q000737:chemistry*; D012016:Reference Values; D015203:Reproducibility of Results; D019279:Resin Cements / Q000737:chemistry*; D033081:Shear Strength; D013499:Surface Properties; D013997:Time Factors
chemical_list: D000538:Aluminum Silicates; D011109:Polymethacrylic Acids; D017680:Potassium Compounds; C462240:RelyX ARC; D019279:Resin Cements; C016447:feldspar; C103502:Variolink; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate