title: Shear bond strength of orthodontic brackets and disinclusion buttons: effect of water and saliva contamination.
abstract: OBJECTIVE
  The aim of this study was to assess the effect of water and saliva contamination on the shear bond strength and failure site of orthodontic brackets and lingual buttons.
  
  
  METHODS
  120 bovine permanent mandibular incisors were randomly divided into 6 groups of 20 specimens each. Both orthodontic brackets and disinclusion buttons were tested under three different enamel surface conditions: (a) dry, (b) water contamination, and (c) saliva contamination. Brackets and buttons were bonded to the teeth and subsequently tested using a Instron universal testing machine. Shear bond strength values and adhesive failure rate were recorded. Statistical analysis was performed using ANOVA and Tukey tests (strength values) and Chi squared test (ARI Scores).
  
  
  RESULTS
  Noncontaminated enamel surfaces showed the highest bond strengths for both brackets and buttons. Under water and saliva contamination orthodontic brackets groups showed significantly lower shear strengths than disinclusion buttons groups. Significant differences in debond locations were found among the groups under the various enamel surface conditions.
  
  
  CONCLUSIONS
  Water and saliva contamination of enamel during the bonding procedure lowers bond strength values, more with orthodontic brackets than with disinclusion buttons.
authors.affiliation: Università degli Studi di Pavia, Dipartimento di Scienze Clinico-Chirurgiche, Diagnostiche e Pediatriche, Sezione di Odontoiatria, Reparto di Ortognatodonzia, Piazzale Golgi 2, 27100 Pavia, Italy.
authors.forename: Maria Francesca
authors.initials: MF
authors.lastname: Sfondrini
authors.forename: Danilo
authors.initials: D
authors.lastname: Fraticelli
authors.forename: Paola
authors.initials: P
authors.lastname: Gandini
authors.forename: Andrea
authors.initials: A
authors.lastname: Scribante
mesh_terms: D000269:Adhesives / Q000494:pharmacology; D000818:Animals; D002417:Cattle; D001840:Dental Bonding; D003743:Dental Enamel / Q000187:drug effects; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D016910:Orthodontic Brackets; D012463:Saliva / Q000737:chemistry*; D033081:Shear Strength / Q000187:drug effects; D014867:Water / Q000737:chemistry*
chemical_list: D000269:Adhesives; D014867:Water