title: Shear bond strength of dentin and deproteinized enamel of amelogenesis imperfecta mouse incisors.
abstract: OBJECTIVE
  The purposes of this study were to: (1) investigate adhesion through shear bond strength (SBS) testing of a resin composite bonded with a self-etching bonding system (SEB) to amelogenesis imperfecta (AI)-affected deproteinized mouse enamel or dentin; and (2) compare wild-type (WT), amelogenin null (AmelxKO), and matrix metalloproteinase-20 null (Mmp20KO) enamel and dentin phenotypes using micro-CT and nanoindentation.
  
  
  METHODS
  Enamel incisor surfaces of WT, AmelxKO, and Mmp20KO mice were treated with SEB with and without sodium hypochlorite and tested for SBS. Incisor dentin was also treated with SEB and tested for SBS. These surfaces were further examined by scanning electron miscroscopy. Micro-CT and nanoindentation analyses were performed on mouse dentin and enamel. Data were analyzed for significance by analysis of variance.
  
  
  RESULTS
  Deproteinization did not improve SBS of SEB to these AI-affected enamel surfaces. SBS of AmelxKO teeth was similar in dentin and enamel; however, it was higher in Mmp20KO dentin. The nanohardness of knockout enamel was significantly lower than WT, while knockout dentin nanohardness was not different from WT.
  
  
  CONCLUSIONS
  Using animal amelogenesis imperfecta models, enamel sodium hypochlorite deproteinization of hypoplastic and hypoplastic-hypomaturation enamel did not increase shear bond strength, while removal of the defective enamel allowed optimal dentin bonding.
authors.affiliation: Department of Mineralized Tissue Biology, The Forsyth Institute, Cambridge, Mass., USA; Department of Developmental Biology, Harvard School of Dental Medicine, Boston, Mass., USA.
authors.forename: Megan K
authors.initials: MK
authors.lastname: Pugach
authors.affiliation: Department of Preventive and Restorative Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pa, USA.
authors.forename: Fusun
authors.initials: F
authors.lastname: Ozer
authors.affiliation: Department of Preventive and Restorative Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pa, USA.
authors.forename: Raj
authors.initials: R
authors.lastname: Mulmadgi
authors.affiliation: Department of Anatomy and Cell Biology, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pa, USA.
authors.forename: Yong
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Pediatric Dentistry, School of Dentistry, University of North Carolina, Chapel Hill, N.C., USA.
authors.forename: Cynthia
authors.initials: C
authors.lastname: Suggs
authors.affiliation: Department of Pediatric Dentistry, School of Dentistry, University of North Carolina, Chapel Hill, N.C., USA.
authors.forename: J Timothy
authors.initials: JT
authors.lastname: Wright
authors.affiliation: Mineralized Tissue Biology, The Forsyth Institute, Cambridge, Mass., USA.
authors.forename: John D
authors.initials: JD
authors.lastname: Bartlett
authors.affiliation: Department of Anatomy and Cell Biology, at the School of Dental Medicine, University of Pennsylvania, Philadelphia, Pa, USA.
authors.forename: Carolyn W
authors.initials: CW
authors.lastname: Gibson
authors.affiliation: Department of Pediatric Dentistry, at the School of Dental Medicine, University of Pennsylvania, Philadelphia, Pa, USA. lindemey@dental.upenn.edu.
authors.forename: Rochelle G
authors.initials: RG
authors.lastname: Lindemeyer
mesh_terms: D000268:Adhesiveness; D000567:Amelogenesis Imperfecta / Q000473:pathology*; D053523:Amelogenin / Q000235:genetics; D000818:Animals; D003188:Composite Resins / Q000737:chemistry; D001840:Dental Bonding; D003743:Dental Enamel / Q000187:drug effects / Q000648:ultrastructure*; D003764:Dental Materials / Q000737:chemistry; D003804:Dentin / Q000187:drug effects / Q000648:ultrastructure*; D006244:Hardness; D007180:Incisor / Q000187:drug effects / Q000648:ultrastructure*; D053519:Matrix Metalloproteinase 20 / Q000235:genetics; D051379:Mice; D018345:Mice, Knockout; D008855:Microscopy, Electron, Scanning; D016877:Oxidants / Q000494:pharmacology; D010641:Phenotype; D019279:Resin Cements / Q000737:chemistry; D033081:Shear Strength; D012973:Sodium Hypochlorite / Q000494:pharmacology; D013314:Stress, Mechanical; D013499:Surface Properties; D055114:X-Ray Microtomography / Q000379:methods
chemical_list: D053523:Amelogenin; C438313:Clearfil SE Bond; D003188:Composite Resins; D003764:Dental Materials; D016877:Oxidants; D019279:Resin Cements; C541508:clearfil majesty; D012973:Sodium Hypochlorite; D053519:Matrix Metalloproteinase 20; C507113:Mmp20 protein, mouse