title: Effect of prerestorative home-bleaching on microleakage of self-etch adhesives.
abstract: BACKGROUND
  Tooth bleaching has become a routine treatment due to patients' esthetic demands.
  
  
  OBJECTIVE
  The aim of this study was to evaluate how prerestorative home-bleaching affected microleakage of resin composite restorations bonded with etch-and-rinse and self-etch adhesives.
  
  
  METHODS
  Fifty extracted human premolar teeth were used. The bleaching agent (10% carbamide peroxide) was applied to the buccal surface of each tooth for 6 hours a day for 2 weeks. The lingual surfaces of the same teeth received no application (control). The teeth were stored in artificial saliva. After 14 days, standardized Class V cavity preparations (2 mm high, 3 mm wide, and 2 mm deep) were made on the buccal and lingual surfaces with all margins in the enamel. They were randomly divided into five groups according to the adhesive systems: an etch-and-rinse adhesive (Single Bond [SB]), two two-step self-etch adhesives (Adper SE Plus [ASE] and One Coat [OC]), and two one-step self-etch adhesives (Adper Easy One [EO] and G-Bond [GB]). All adhesives were applied according to the manufacturers' instructions. The preparations were then restored using the same hybrid composite (Filtek Z250) in one increment and light-cured. The teeth were thermocycled (5/55 degrees C, 1,000x) and immersed in dye, then sectioned, and dye penetration was scored. The data were analyzed using the Kruskal-Wallis and Mann-Whitney U-tests.
  
  
  RESULTS
  Although statistically significant differences were found between the adhesive systems in the bleached teeth, no differences were observed in the control groups (non-bleached teeth). There were significant differences between SB/GB, SB/EO, SB/OC, and GB/ASE in the bleached teeth (p < 0.05). When comparing bleached and non-bleached teeth within each adhesive system, only SB and EO produced higher leakage scores when bleaching was applied. The other groups showed no difference in terms of bleaching (p > 0.05).
  
  
  CONCLUSIONS
  Prerestorative home-bleaching had an adverse effect on microleakage of SB and EO.
  
  
  CONCLUSIONS
  The effect of prerestorative home-bleaching agents on microleakage of composite resin restorations differs according to the type of adhesive material used.
authors.affiliation: Faculty of Dentistry, Department of Conservative Dentistry, Hacettepe University, Sihhiye, Ankara, Turkey. ruyay@hacettepe.edu.tr
authors.forename: A Rüya
authors.initials: AR
authors.lastname: Yazici
authors.forename: Asli
authors.initials: A
authors.lastname: Keleş
authors.forename: Duygu
authors.initials: D
authors.lastname: Tuncer
authors.forename: Meserret
authors.initials: M
authors.lastname: Başeren
mesh_terms: D001641:Bicuspid; D017438:Bisphenol A-Glycidyl Methacrylate / Q000009:adverse effects*; D000077463:Carbamide Peroxide; D003188:Composite Resins / Q000528:radiation effects; D003743:Dental Enamel / Q000187:drug effects; D045662:Dental Etching / Q000379:methods; D003763:Dental Leakage / Q000209:etiology*; D003793:Dental Restoration, Permanent; D006801:Humans; D055115:Light-Curing of Dental Adhesives; D016877:Oxidants / Q000009:adverse effects*; D010545:Peroxides / Q000009:adverse effects*; D019279:Resin Cements / Q000009:adverse effects*; D014073:Tooth Bleaching / Q000009:adverse effects*; D014508:Urea / Q000009:adverse effects / Q000031:analogs & derivatives*
chemical_list: C000612360:Adper Easy One; D003188:Composite Resins; C444701:Filtek Z250; D016877:Oxidants; D010545:Peroxides; D019279:Resin Cements; D000077463:Carbamide Peroxide; D017438:Bisphenol A-Glycidyl Methacrylate; D014508:Urea