title: Degree of conversion of two-step etch-and-rinse adhesives: In situ micro-Raman analysis.
abstract: OBJECTIVE
  DC of three commercial two-step etch-and-rinse adhesives across the dentine-adhesive interface was investigated using micro-Raman spectroscopy. The hypothesis tested was that no difference in DC would exist among the adhesives tested.
  
  
  METHODS
  Adper Scotchbond 1XT (3M ESPE), Prime&Bond NT (Dentsply DeTrey), and Ambar (FGM) were applied on human dentine disks (n=9). Composite increments of 2mm were then applied on the adhesive surface. Raman spectra were collected along the dentine-adhesive interface. The relative intensities of the peaks associated with the mineral (PO(4)(3-) at 960cm(-1)) and the adhesive (CC at 1640cm(-1); phenyl CC at 1610cm(-1)) were used to identify the adhesive within the hybrid layer and calculate its DC.
  
  
  RESULTS
  Adper Scotchbond 1XT and Ambar showed similar DC (79±7% and 77±7%, respectively), while a lower DC was found for Prime&Bond NT (70±7%; p<0.05).
  
  
  CONCLUSIONS
  The hypothesis tested was rejected because differences were found among the adhesives tested. The difference in DC among the three adhesive systems can be attributed to different monomer compositions and solvents. Further studies are needed to correlate DC with other mechanical properties of these adhesives.
  
  
  CONCLUSIONS
  Insufficient polymerization of an adhesive can result in a weak hybrid layer, and the presence of unreacted monomers may result in degradation of the polymeric network, decreasing the strength and longevity of the bond. In the present study, Adper Scotchbond 1XT and Ambar performed significantly better than Prime&Bond NT.
authors.affiliation: Department of Medical Sciences, University of Trieste, Piazza dell'Ospitale 1, 5 Trieste, Italy.
authors.forename: Chiara Ottavia
authors.initials: CO
authors.lastname: Navarra
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Breschi
authors.forename: Gianluca
authors.initials: G
authors.lastname: Turco
authors.forename: Marina
authors.initials: M
authors.lastname: Diolosà
authors.forename: Luca
authors.initials: L
authors.lastname: Fontanive
authors.forename: Lucia
authors.initials: L
authors.lastname: Manzoli
authors.forename: Roberto
authors.initials: R
authors.lastname: Di Lenarda
authors.forename: Milena
authors.initials: M
authors.lastname: Cadenaro
mesh_terms: D000134:Acid Etching, Dental; D002244:Carbon / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry; D001840:Dental Bonding; D003764:Dental Materials / Q000737:chemistry; D003804:Dentin / Q000648:ultrastructure*; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D006801:Humans; D006859:Hydrogen / Q000737:chemistry; D055115:Light-Curing of Dental Adhesives; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D009584:Nitrogen / Q000737:chemistry; D010100:Oxygen / Q000737:chemistry; D010710:Phosphates / Q000737:chemistry; D058105:Polymerization; D011109:Polymethacrylic Acids / Q000737:chemistry; D011140:Polyurethanes / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000379:methods; D013499:Surface Properties; D013997:Time Factors
chemical_list: D003188:Composite Resins; D003764:Dental Materials; D017220:Dentin-Bonding Agents; C444701:Filtek Z250; D008689:Methacrylates; D010710:Phosphates; D011109:Polymethacrylic Acids; D011140:Polyurethanes; C425843:Prime and Bond NT; D019279:Resin Cements; C029824:urethane dimethacrylate luting resin; C005044:hydroxyethyl methacrylate; D002244:Carbon; D006859:Hydrogen; C041330:Scotchbond; D009584:Nitrogen; D010100:Oxygen