title: Chemical interaction of 10-MDP (methacryloyloxi-decyl-dihydrogen-phosphate) in zinc-doped self-etch adhesives.
abstract: OBJECTIVE
  Zinc-doped dentine adhesives have been recently advocated to interfere with metallo-proteinases-mediated collagen degradation. Nevertheless, there is a little information about the effects of zinc ions on the chemical interaction of self-etch functional monomers to dentine. The aim of this study was to assess if the inclusion of zinc into the primers of self-etch adhesives containing MDP (10-methacryloyloxi-decyl-dihydrogen-phosphate) may interfere with their chemical interaction to calcium/dentine.
  
  
  METHODS
  Caries-free human molars were bonded using two commercial self-etching adhesives [Clearfil SE bond (CSE) and S3 bond (S3)] doped with zinc nitrate and submitted to microtensile bond strength (μTBS) and interface nanoleakage evaluation. Moreover, MDP was synthesised to evaluate the chemical interaction with calcium/dentine through atomic absorption spectroscopy (AAS) and SEM-EDX in the presence or absence of zinc ions.
  
  
  RESULTS
  AAS showed increasing formation of MDP-zinc rather than MDP-calcium salts (p=0.002) in the presence of zinc. SEM-EDX confirmed the formation of zinc-rich phosphate deposits that were probably responsible for the significant reduction in μTBS and increased interfacial nanoleakage attained with zinc-doped CSE and S3.
  
  
  CONCLUSIONS
  These outcomes demonstrated that the excessive presence of zinc ions may jeopardise the bonding performance of MDP-containing self-etch adhesives.
authors.affiliation: Division of Dental Materials, Piracicaba Dental School, State University of Campinas, Piracicaba, SP, Brazil. Electronic address: victorpfeitosa@hotmail.com.
authors.forename: Victor P
authors.initials: VP
authors.lastname: Feitosa
authors.affiliation: Division of Dental Materials, Piracicaba Dental School, State University of Campinas, Piracicaba, SP, Brazil. Electronic address: cesar.pomacondor.hernandez@gmail.com.
authors.forename: César
authors.initials: C
authors.lastname: Pomacóndor-Hernández
authors.affiliation: Materials Engineering School, Federal University of Pelotas, Pelotas, Brazil. Electronic address: ogliari@gmail.com.
authors.forename: Fabrício A
authors.initials: FA
authors.lastname: Ogliari
authors.affiliation: Materials Engineering School, Federal University of Pelotas, Pelotas, Brazil. Electronic address: fernandableal@gmail.com.
authors.forename: Fernanda
authors.initials: F
authors.lastname: Leal
authors.affiliation: Division of Dental Materials, Piracicaba Dental School, State University of Campinas, Piracicaba, SP, Brazil.
authors.forename: Américo B
authors.initials: AB
authors.lastname: Correr
authors.affiliation: Dental Biomaterials Departamento de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad CEU Cardenal Herrera, Valencia, Spain. Electronic address: salvatore.sauro@uch.ceu.es.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Sauro
mesh_terms: D002118:Calcium / Q000737:chemistry; D001840:Dental Bonding; D003763:Dental Leakage / Q000145:classification; D003804:Dentin / Q000648:ultrastructure*; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D009566:Nitrates / Q000737:chemistry; D010710:Phosphates / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D013052:Spectrometry, X-Ray Emission; D013054:Spectrophotometry, Atomic; D017550:Spectroscopy, Fourier Transform Infrared; D013314:Stress, Mechanical; D013718:Tensile Strength; D015032:Zinc / Q000737:chemistry*; D017967:Zinc Compounds / Q000737:chemistry
chemical_list: C505694:Clearfil S3 Bond; C438313:Clearfil SE Bond; D017220:Dentin-Bonding Agents; D008689:Methacrylates; D009566:Nitrates; D010710:Phosphates; D019279:Resin Cements; D017967:Zinc Compounds; C043952:zinc phosphate; C069749:methacryloyloxydecyl dihydrogen phosphate; C042103:zinc nitrate; D015032:Zinc; D002118:Calcium
keywords: Chemical interaction; Dentine adhesion; Functional monomers; Self-etch adhesives; Zinc ions