title: Shear bond strength comparison of a conventional and a self-etching fluoride-releasing adhesive following thermocycling.
abstract: OBJECTIVE
  To compare the effect of thermocycling on the shear bond strength of brackets bonded using different primers.
  
  
  METHODS
  One hundred twenty extracted defect-free premolars were randomly divided into three groups. In all three, Transbond XT was the bonding adhesive of choice. In the control group (I), the standard Transbond primer was used, in group II a fluoride-releasing primer (Reliance fluoride containing light cure bond), and in group III an antimicrobial fluoride-releasing self-etching primer (Clearfil Protect Bond). These three groups were divided into two subgroups of 20 teeth each. In the first subgroups, the teeth were stored in only distilled water for 24 hours, whereas in the second subgroups, they were thermocycled 500 times between 5 degrees C and 55 degrees C. The shear bond strength was determined with a universal testing machine. After bracket failure, the Adhesive Remnant Index (ARI) score was verified. The data were analyzed using two-way analysis of variance, Bonferroni, and chi-square tests.
  
  
  RESULTS
  The group with the antimicrobial fluoride-releasing self-etching primer had a significantly lower shear bond strength than all other groups (P<.05). Thermocycling reduced the shear bond strength in all groups considerably.
  
  
  CONCLUSIONS
  The antimicrobial fluoride-releasing self-etching primer performed comparably worse regardless of thermocycling. Brackets attached with self-etching primers demonstrated a shear bond strength after thermocycling approaching the border of acceptable adhesion. Thermocycling changed the ARI scores of the self-etching primer groups from the bracket-adhesive to the enamel-adhesive interface.
authors.affiliation: Department of Orthodontics, Faculty of Dentistry, Gaziantep University, Sahinbey, Gaziantep, Turkey. almanoral@hotmail.com
authors.forename: Oral
authors.initials: O
authors.lastname: Sökücü
authors.forename: Şeyda Hergüner
authors.initials: ŞH
authors.lastname: Siso
authors.forename: Özden Özel
authors.initials: ÖÖ
authors.lastname: Bektaş
authors.forename: Hasan
authors.initials: H
authors.lastname: Babacan
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D000268:Adhesiveness; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003799:Dental Stress Analysis / Q000295:instrumentation; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D016910:Orthodontic Brackets; D019279:Resin Cements / Q000737:chemistry*; D033081:Shear Strength; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000737:chemistry
chemical_list: C503075:Clearfil Protect Bond; D003188:Composite Resins; D017220:Dentin-Bonding Agents; C090340:Reliance resin cement; D019279:Resin Cements; C477790:Transbond XT; C516047:Transbond XT Light Cure Adhesive Primer; D014867:Water