title: Artificial saliva contamination effects on bond strength of self-etching primers.
abstract: OBJECTIVE
  To test the hypothesis that there is no difference in the bond strength with or without contamination with artificial saliva when using two different self-etching primers (Transbond Plus and iBond) in comparison with a conventional acid-etching method (37% phosphoric acid and Transbond XT) for bonding of orthodontic brackets.
  
  
  METHODS
  One hundred fifty extracted human premolars were randomly allocated to six different groups, with 25 teeth in each group. Orthodontic metal brackets (APC II, Victory Twin 22 UNIV) were used. For contamination, a saliva replacement (Ptyalin) was applied. After contamination the surface was air-dried for 5 seconds and the bonding procedure continued. The bonded teeth were stored in deionized water at 37 degrees C for 30 days and then thermocycled for 24 hours before debonding with a universal testing machine. The load was recorded at bond failure. The location of adhesive failure was determined under magnification using the adhesive remnant index (ARI).
  
  
  RESULTS
  Clinically acceptable bond strengths were found for all primers used in this study. The contamination by saliva significantly decreased the bond strength when using the conventional acid-etching method (t = 0.0001). Self-etching primers were less influenced by saliva contamination. There was no significant difference in the ARI score among the groups (P > .05).
  
  
  CONCLUSIONS
  Saliva contamination significantly decreased the bond strength when the conventional acid-etching method was used. The self-etching primers were influenced the least. The bond strengths achieved for the self-etching primers and the conventional etching method after saliva contamination were not significantly different.
authors.affiliation: Department of Orthodontics, Dental School, Ludwig-Maximilians-University, Munich, Germany. epaschos@med.uni-muenchen.de
authors.forename: Ekaterini
authors.initials: E
authors.lastname: Paschos
authors.forename: Jean-Oliver
authors.initials: JO
authors.lastname: Westphal
authors.forename: Nicoleta
authors.initials: N
authors.lastname: Ilie
authors.forename: Karin Christine
authors.initials: KC
authors.lastname: Huth
authors.forename: Reinhard
authors.initials: R
authors.lastname: Hickel
authors.forename: Ingrid
authors.initials: I
authors.lastname: Rudzki-Janson
mesh_terms: D000704:Analysis of Variance; D001641:Bicuspid; D001840:Dental Bonding; D045662:Dental Etching / Q000379:methods*; D003799:Dental Stress Analysis; D006801:Humans; D008422:Materials Testing; D016910:Orthodontic Brackets; D019279:Resin Cements; D012464:Saliva, Artificial; D016019:Survival Analysis
chemical_list: D019279:Resin Cements; D012464:Saliva, Artificial; C429625:Transbond Plus Self-Etching Primer; C477386:iBond