title: Phosphoric acid and copper (II) sulphate as a combined etchant and activator prior to the use of an anaerobic adhesive.
abstract: OBJECTIVE
  Previous work has shown that steel attachments can be bonded to etched human enamel using anaerobic adhesives, following treatment with a solution of 0.05M copper (II) sulphate. The objectives of this experiment were to determine whether simultaneous etching and activation could be performed with a combined solution of o-phosphoric acid and copper (II) sulphate.
  
  
  METHODS
  Stainless steel attachments were bonded to human enamel using an anaerobic adhesive. In each case the enamel was etched and activated using a solution of 37% o-phosphoric acid containing various concentrations of copper (II) sulphate. After bench curing for one hour, the specimens were shear bond tested to failure and the load at debond recorded in each case. Following determination of the optimum copper (II) sulphate concentration the experiment was repeated, but this time the acid was made into a gel using colloidal silica. The effect of rinse time after etching was also investigated with the gel.
  
  
  RESULTS
  The results were analysed using mean force to debond (N) and 95% confidence intervals. Kaplan-Meier survival probabilities and log rank tests were also performed. Under the conditions of this experiment the optimum concentration of copper (II) sulphate was found to be 1M. When the acid was made into a gel the optimum rinsing time was found to be 60s.
  
  
  CONCLUSIONS
  This experiment demonstrates that steel attachments can be bonded to enamel using anaerobic adhesives where the enamel has been simultaneously etched and activated. A combined o-phosphoric acid and copper (II) sulphate solution or gel can be used, but a conventional etch pattern is not produced.
authors: Department of Orthodontics, Royal United Hospital, Combe Park, Bath BA1 4DP, UK.
authors: A J
authors: AJ
authors: Ireland
authors: M
authors: M
authors: Sherriff
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods*; D001641:Bicuspid; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry*; D019327:Copper Sulfate / Q000737:chemistry / Q000494:pharmacology; D003738:Dental Cements / Q000737:chemistry*; D017005:Dental Debonding; D003743:Dental Enamel / Q000187:drug effects*; D003799:Dental Stress Analysis; D005782:Gels / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D016910:Orthodontic Brackets; D010756:Phosphoric Acids / Q000737:chemistry / Q000494:pharmacology; D011108:Polymers / Q000737:chemistry; D013193:Stainless Steel; D013499:Surface Properties / Q000187:drug effects; D016019:Survival Analysis
chemical_list: D003738:Dental Cements; D005782:Gels; C400047:Perma Metal; D010756:Phosphoric Acids; D011108:Polymers; D013193:Stainless Steel; D017438:Bisphenol A-Glycidyl Methacrylate; C030242:phosphoric acid; D019327:Copper Sulfate