title: Effect of moisture on dental enamel in the interaction of two orthodontic bonding systems.
abstract: OBJECTIVE
  The purpose of this study was to assess by means of scanning electron microscopy (SEM) the remaining adhesive interface after debonding orthodontic attachments bonded to bovine teeth with the use of hydrophilic and hydrophobic primers under different dental substrate moisture conditions.
  
  
  METHODS
  Twenty mandibular incisors were divided into four groups (n = 5). In Group I, bracket bonding was performed with Transbond MIP hydrophilic primer and Transbond XT adhesive paste applied to moist substrate, and in Group II a bonding system comprising Transbond XT hydrophobic primer and adhesive paste was applied to moist substrate. Brackets were bonded to the specimens in Groups III and IV using the same adhesive systems, but on dry dental enamel. The images were qualitatively assessed by SEM.
  
  
  RESULTS
  The absence of moisture in etched enamel enabled better interaction between bonding materials and the adamantine structure. The hydrophobic primer achieved the worst micromechanical interlocking results when applied to a moist dental structure, whereas the hydrophilic system proved versatile, yielding acceptable results in moist conditions and excellent interaction in the absence of contamination.
  
  
  CONCLUSIONS
  The authors assert that the best condition for the application of primers to dental enamel occurs in the absence of moisture.
authors.forename: André Pinheiro de Magalhães
authors.initials: AP
authors.lastname: Bertoz
authors.forename: Derly Tescaro Narcizo
authors.initials: DT
authors.lastname: de Oliveira
authors.forename: Carla Maria Melleiro
authors.initials: CM
authors.lastname: Gimenez
authors.forename: André Luiz Fraga
authors.initials: AL
authors.lastname: Briso
authors.forename: Francisco Antonio
authors.initials: FA
authors.lastname: Bertoz
authors.forename: Eduardo César Almada
authors.initials: EC
authors.lastname: Santos
mesh_terms: D000818:Animals; D002417:Cattle; D001840:Dental Bonding / Q000379:methods; D003738:Dental Cements / Q000737:chemistry*; D017005:Dental Debonding; D003743:Dental Enamel / Q000737:chemistry*; D000431:Ethanol / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D007180:Incisor; D008334:Mandible; D008689:Methacrylates / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D016910:Orthodontic Brackets; D019279:Resin Cements / Q000737:chemistry*; D013499:Surface Properties; D014867:Water
chemical_list: D003738:Dental Cements; D008689:Methacrylates; D019279:Resin Cements; C477790:Transbond XT; C458821:Transbond moisture-insensitive primer; D014867:Water; D000431:Ethanol
keywords: Dental primer; Orthodontic brackets; Scanning electron microscopy