title: Modifications of the organic and mineral fractions of dental tissues following conditioning by self-etching adhesives.
abstract: OBJECTIVE
  Our objective was to analyse the acid strengths and concentrations in contemporary self-etch adhesives and test whether the adhesion/decalcification concept functions the same way for all products.
  
  
  METHODS
  The self-etching adhesives were dissolved in a 50% water-ethanol solvent, these were reacted with biological apatite (HA) in the form of powder of human dentine in order to quantify calcium release and study the reaction products as a function of acid strengths and concentrations. The four self-etching adhesives investigated were AdheSE One (Ivoclar Vivadent, Schaan, Liechtenstein), Adper Easy Bond (3M ESPE, St Paul, MN, USA), Optibond All-In-One (KERR, Orange, CA, USA), Xeno V (Dentsply De Trey, Konstanz, Germany).
  
  
  RESULTS
  Acid concentrations were found to span the range from 1 to 2 mmol/l, and the acid dissociation constants varied between apparent pKa values of 3.4 and 4.2. The pH values changed with time from values near 2.8 to 3.6, confirming the buffering action of HA. The stronger acids dissolved more calcium ions but left less organic matter attached to the tissue particles. Thermogravimetric and infrared analysis demonstrated that the weaker acids tended to bind to HA surfaces and increased significantly the organic to mineral ratios of the powders.
  
  
  CONCLUSIONS
  Self-etching adhesives can be differentiated and classified in two types: weak acids attach to the mineral phase and leach little calcium; strong acids bind to the calcium ions, demineralize more and tend to debond from the dentinal hard tissues by forming more soluble calcium salts.
authors.affiliation: Department of Biomaterials, Faculty of Odontology, University Toulouse III, 31062 Toulouse, France.
authors.forename: Farimata
authors.initials: F
authors.lastname: Dieng-Sarr
authors.forename: Patrick
authors.initials: P
authors.lastname: Sharrock
authors.forename: Firas
authors.initials: F
authors.lastname: Dabsie
authors.forename: Geneviève
authors.initials: G
authors.lastname: Grégoire
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods*; D000143:Acids / Q000737:chemistry; D000178:Acrylamides / Q000737:chemistry; D000180:Acrylic Resins / Q000737:chemistry; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D002021:Buffers; D002118:Calcium / Q000032:analysis; D055598:Chemical Phenomena; D001840:Dental Bonding; D003804:Dentin / Q000737:chemistry*; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D017886:Durapatite / Q000737:chemistry; D000431:Ethanol / Q000737:chemistry; D006801:Humans; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D012995:Solubility; D012997:Solvents / Q000737:chemistry; D013055:Spectrophotometry, Infrared; D013818:Thermogravimetry; D017186:Titrimetry; D014867:Water / Q000737:chemistry
chemical_list: D000143:Acids; D000178:Acrylamides; D000180:Acrylic Resins; C489662:AdheSE cement; D002021:Buffers; D017220:Dentin-Bonding Agents; D008689:Methacrylates; C092987:Optibond; D019279:Resin Cements; D012997:Solvents; D014867:Water; D000431:Ethanol; D017438:Bisphenol A-Glycidyl Methacrylate; C005044:hydroxyethyl methacrylate; D017886:Durapatite; D002118:Calcium