title: Effects of different chlorhexidine pretreatments on adhesion of metal brackets in vitro.
abstract: OBJECTIVE
  To investigate the effect of chlorhexidine applications in various forms and concentrations on adhesion and failure modes of metal brackets in vitro.
  
  
  METHODS
  Ninety bovine enamel specimens were allocated to six groups (n=15). Metal brackets were bonded on all specimens after chlorhexidine pre-treatments forming the following groups: (1) untreated specimens (control); (2) 40% varnish (EC40, Biodent BV, Netherlands), remnants removed with brushing mimicking patient cleaning; (3) 40% varnish (EC40), remnants removed with brushing mimicking professional cleaning; (4) 1% varnish (Cervitec Plus, Ivoclar vivadent, Schaan, Liechtenstein), remnants not removed; (5) brushed with% 1 gel (Corsodyl, GlaxoSmithKline, Münchenbuchsee, Germany), remnants not removed; (6) immersed in 0.07% mouthrinse (Corsodyl, GlaxoSmithKline, Münchenbuchsee, Germany), remnant not rinsed. Debonding of brackets was performed using a universal testing machine. Data were analysed using one-way ANOVA and post-hoc Scheffé test.
  
  
  RESULTS
  Group 4 performed significantly inferior than all the other groups and the control. Group 4 presented the highest number of adhesive failures at the enamel-resin interface whereas in other groups no failures at adhesive-resin interface was observed.
  
  
  CONCLUSIONS
  Presence of chlorhexidine varnish prior to bracket bonding adversely affects adhesion. Concentration of chlorhexidine pre-treatment has no influence on shear bond strength.
authors.affiliation: Department of Orthodontics, University of Ege, Izmir, Turkey.
authors.forename: Corinne
authors.initials: C
authors.lastname: Frey
authors.forename: Enver
authors.initials: E
authors.lastname: Yetkiner
authors.forename: Bogna
authors.initials: B
authors.lastname: Stawarczyk
authors.forename: Thomas
authors.initials: T
authors.lastname: Attin
authors.forename: Rengin
authors.initials: R
authors.lastname: Attin
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D000891:Anti-Infective Agents, Local / Q000737:chemistry / Q000494:pharmacology; D002417:Cattle; D002710:Chlorhexidine / Q000737:chemistry / Q000494:pharmacology*; D016001:Confidence Intervals; D001840:Dental Bonding / Q000379:methods*; D017005:Dental Debonding / Q000379:methods; D003743:Dental Enamel / Q000187:drug effects* / Q000378:metabolism; D003799:Dental Stress Analysis / Q000379:methods*; D004305:Dose-Response Relationship, Drug; D066298:In Vitro Techniques; D007180:Incisor / Q000187:drug effects; D016910:Orthodontic Brackets; D012016:Reference Values; D012680:Sensitivity and Specificity; D033081:Shear Strength
chemical_list: D000891:Anti-Infective Agents, Local; D002710:Chlorhexidine