title: Mechanical properties of components of the bonding interface in different regions of radicular dentin surfaces.
abstract: BACKGROUND
  The mechanical properties of the adhesive materials used in intraradicular treatments could vary according to the interaction between the restorative material and dentin substrate. An evaluation of these properties is essential to determine the success of the luting procedures performed on glass-fiber posts.
  
  
  OBJECTIVE
  The purpose of this study was to evaluate the mechanical properties of dentin adhesives, resin cements, and the dentin that underlies the bonding interface in different thirds of intraradicular dentin.
  
  
  METHODS
  Forty extracted, single-rooted human teeth were used in this study. After the endodontic treatment of the post spaces, the teeth were divided into 5 groups (n=8): Adper Single Bond 2 + RelyX ARC, Excite DSC + RelyX ARC, Adper SE Plus + RelyX ARC, RelyX Unicem, and Set. The hardness and elastic modulus values were measured at the adhesive interface in different thirds of the radicular dentin by using an ultramicrohardness tester. The data were subjected to 2-way ANOVA and the Fisher protected least significant difference test (α=.05).
  
  
  RESULTS
  In the underlying dentin, the highest Martens hardness values were found in the apical region for all groups; the exceptions were the groups with the self-etching adhesive. In the adhesive layer, the highest Martens hardness values were obtained for the Adper SE Plus + RelyX ARC group; further, no statistical differences were found among the different regions for this group. RelyX ARC had the lowest Martens hardness and elastic modulus values in the apical regions when used with Adper Single Bond 2 and Adper SE Plus. No differences were found in the Martens hardness and elastic modulus values for the self-adhesive resin cement in the regions investigated.
  
  
  CONCLUSIONS
  The mechanical properties of adhesive materials and the underlying dentin are influenced by the interaction between the two as well as by the depth of the analyzed intraradicular area.
authors.affiliation: Postgraduate student, Department of Dental Materials and Prosthodontics, Araçatuba School of Dentistry, Sao Paulo State University (UNESP), Araçatuba, Brazil.
authors.forename: Thaís Yumi Umeda
authors.initials: TY
authors.lastname: Suzuki
authors.affiliation: Associate Professor, Department of Restorative Dentistry, Araçatuba School of Dentistry, Sao Paulo State University (UNESP), Araçatuba, Brazil.
authors.forename: João Eduardo
authors.initials: JE
authors.lastname: Gomes-Filho
authors.affiliation: Associate Professor, Department of Mechanical Engineering, Ilha Solteira School of Engineering, Sao Paulo State University (UNESP), Ilha Solteira, Brazil.
authors.forename: Juno
authors.initials: J
authors.lastname: Gallego
authors.affiliation: Assistant Professor, Department of Dentistry, Adamantina School of Dentistry (FAI), Adamantina, Brazil.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Pavan
authors.affiliation: Associate Professor, Department of Dental Materials and Prosthodontics, Araçatuba School of Dentistry, Sao Paulo State University (UNESP), Araçatuba, Brazil. Electronic address: paulosantos@foa.unesp.br.
authors.forename: Paulo Henrique
authors.initials: PH
authors.lastname: Dos Santos
authors.affiliation: Associate Professor, Department of Restorative Dentistry, Araçatuba School of Dentistry, Sao Paulo State University (UNESP), Araçatuba, Brazil.
authors.forename: André Luiz
authors.initials: AL
authors.lastname: Fraga Briso
mesh_terms: D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D001840:Dental Bonding; D003738:Dental Cements / Q000737:chemistry; D003764:Dental Materials / Q000737:chemistry; D003786:Dental Pulp Cavity / Q000648:ultrastructure*; D003804:Dentin / Q000648:ultrastructure*; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D055119:Elastic Modulus; D005898:Glass / Q000737:chemistry; D006244:Hardness; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D011176:Post and Core Technique / Q000295:instrumentation; D019279:Resin Cements / Q000737:chemistry; D018915:Root Canal Preparation / Q000379:methods; D013314:Stress, Mechanical; D019227:Tooth Apex / Q000648:ultrastructure
chemical_list: C554641:Adper single bond 2; D003738:Dental Cements; D003764:Dental Materials; D017220:Dentin-Bonding Agents; C420130:Excite cement; D008689:Methacrylates; D011109:Polymethacrylic Acids; C483701:Rely X Unicem; C462240:RelyX ARC; D019279:Resin Cements; C009753:fiberglass; C020946:triethylene glycol dimethacrylate; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate; C005044:hydroxyethyl methacrylate; C028643:trimethylolpropane trimethacrylate