title: Comparative evaluation of shear bond strength of metallic brackets bonded with two different bonding agents under dry conditions and with saliva contamination.
abstract: BACKGROUND
  This study compared the shear bond strength of metallic brackets bonded with Single Bond and Assure bonding agents under dry and saliva-contamination conditions.
  
  
  METHODS
  Sixty sound premolar teeth were selected, and stainless-steel brackets were bonded on enamel surfaces with Single Bond and Assure bonding agents under dry condition or with saliva contamination. Shear bond strength values of brackets were measured in a universal testing machine. The adhesive remnant index scores were determined after debonding of the brackets under a stereomicroscope. One-way analysis of variance (ANOVA) was used to analyze bond strength. Two-by-two comparisons were made with post hoc Tukey tests (p<0.001). Frequencies of adhesive remnant index scores were analyzed by Kruskal-Wallis test.
  
  
  RESULTS
  Bond strength values of brackets to tooth structure were 9.29±8.56 MPa and 21.25±8.93 MPa with the use of Assure resin bonding agent under saliva-contamination and dry conditions, respectively. These values were 10.13±6.69 MPa and 14.09±6.6 MPa, respectively, under the same conditions with the use of Single Bond adhesive. Contamination with saliva resulted in a significant decrease in the bond strength of brackets to tooth structure with the application of Assure adhesive resin (p<0.001). There were no significant differences in the adhesive remnant index scores between the study groups.
  
  
  CONCLUSIONS
  Application of Single Bond and Assure bonding agents resulted in adequate bond strength of brackets to tooth structures. Contamination with saliva significantly decreased the bond strength of Assure bonding agent compared with dry conditions.
authors.affiliation: Department of orthodontics, Dental School, Ahwaz Jundishapur University of Medical Sciences, Iran. Electronic address: masjedi_kh@yahoo.com.
authors.forename: Mashallah
authors.initials: M
authors.lastname: Khanehmasjedi
authors.affiliation: School of Dentistry, Azad University of Medical Sciences, Borujerd, Iran.
authors.forename: Mohammad Ali
authors.initials: MA
authors.lastname: Naseri
authors.affiliation: Department of orthodontics, Dental School, Ahwaz Jundishapur University of Medical Sciences, Iran; School of Dentistry, Azad University of Medical Sciences, Borujerd, Iran.
authors.forename: Samaneh
authors.initials: S
authors.lastname: Khanehmasjedi
authors.affiliation: Department of orthodontics, Dental School, Ahwaz Jundishapur University of Medical Sciences, Iran.
authors.forename: Leila
authors.initials: L
authors.lastname: Basir
mesh_terms: D017438:Bisphenol A-Glycidyl Methacrylate; D017220:Dentin-Bonding Agents / Q000494:pharmacology*; D006801:Humans; D016910:Orthodontic Brackets; D012463:Saliva / Q000737:chemistry*; D033081:Shear Strength
chemical_list: D017220:Dentin-Bonding Agents; C115612:single bond; D017438:Bisphenol A-Glycidyl Methacrylate
keywords: Assure universal bonding resin; Single Bond adhesive resin; shear bond strength