title: Effect of light-cured filled sealant on shear bond strength of metal and ceramic brackets bonded with a resin-modified glass ionomer cement.
abstract: BACKGROUND
  Our objective was to evaluate the effects of a highly filled light-cured sealant (HFLCS) on the shear bond strength and bond failure site of metal and ceramic brackets bonded with resin-modified glass ionomer cement (RMGIC).
  
  
  METHODS
  Eighty freshly extracted maxillary premolars were randomly divided into 4 groups (20 in each group). In all groups, the teeth were etched with 37% phosphoric acid for 20 seconds, and RMGIC (Fuji Ortho LC, GC Europe, Leuven, Belgium) was used for bracket bonding. In groups 1 and 3, the brackets were bonded directly to etched enamel surfaces; in groups 2 and 4, the etched enamel was covered with HFLCS (Pro Seal, Reliance Orthodontic Products, Itasca, Ill). Groups 1 and 2 received metal brackets, and groups 3 and 4 had ceramic brackets. The specimens were stored in distilled water at room temperature for 24 hours and subsequently tested in shear mode with a universal testing machine. After debonding, the teeth and the brackets were examined under a stereomicroscope (model SMZ-1B, Nikon, Osaka, Japan) at 20-times magnification to assess the residual adhesive on the tooth surfaces.
  
  
  RESULTS
  Interaction between HFLCS and bracket type was not statistically significant (P = 0.15). Pretreatment with HFLCS did not cause a statistically significant change in the shear bond values of either metal or ceramic brackets (P = 0.38). Shear bond values of the ceramic brackets were higher than those of the metal brackets independent of HFLCS application (P <0.001). No significant differences were found in bond failure modes in the 4 groups.
  
  
  CONCLUSIONS
  HFLCS application on enamel etched with 37% phosphoric acid did not affect the bond strength values and the bond failure modes of metal and ceramic brackets bonded with RMGIC.
  
  
  RESULTS
  Interaction between HFLCS and bracket type was not statistically significant (P = 0.15). Pretreatment with HFLCS did not cause a statistically significant change in the shear bond values of either metal or ceramic brackets (P = 0.38). Shear bond values of the ceramic brackets were higher than those of the metal brackets independent of HFLCS application (P <0.001). No significant differences were found in bond failure modes in the 4 groups.
  
  
  CONCLUSIONS
  HFLCS application on enamel etched with 37% phosphoric acid did not affect the bond strength values and the bond failure modes of metal and ceramic brackets bonded with RMGIC.
authors.affiliation: Department of Orthodontics, Faculty of Dentistry, Gazi University, Ankara, Turkey. kaleselin@yahoo.com
authors.forename: Selin Kale
authors.initials: SK
authors.lastname: Varlik
authors.forename: Cağri
authors.initials: C
authors.lastname: Ulusoy
mesh_terms: D000134:Acid Etching, Dental; D000180:Acrylic Resins / Q000737:chemistry; D000538:Aluminum Silicates / Q000737:chemistry; D002516:Ceramics / Q000737:chemistry*; D003722:Dental Alloys / Q000737:chemistry*; D003743:Dental Enamel / Q000473:pathology; D005899:Glass Ionomer Cements / Q000737:chemistry*; D006801:Humans; D055115:Light-Curing of Dental Adhesives; D008422:Materials Testing; D016382:Orthodontic Appliance Design; D016910:Orthodontic Brackets; D010756:Phosphoric Acids / Q000737:chemistry; 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: D000180:Acrylic Resins; D000538:Aluminum Silicates; D003722:Dental Alloys; C095451:Fuji Ortho LC; D005899:Glass Ionomer Cements; D010756:Phosphoric Acids; C501632:Pro Seal; D019279:Resin Cements; D014867:Water; C030242:phosphoric acid