title: The effect of pre-etching with 37% orthophosphoric acid on the shear bond strength of orthodontic brackets bonded using self-etching primer-adhesive system.
abstract: OBJECTIVE
  The purpose of this study was to compare the effect of pre-etching with 37% orthophosphoric acid on the shear bond strength (SBS) of orthodontic brackets bonded using self-etching primer (SEP).
  
  
  METHODS
  Two hundred freshly extracted human premolars were divided randomly into two groups based on pre-etching with 37% orthophosphoric acid: Group 1 (control, n = 50) without pre-etching and Group 2 (experimental, n = 150) with pre-etching. Group 2 was further divided into three sub groups 2a, 2b, and 2c with 50 teeth each and was first pre-etched with 37% orthophosphoric acid for 10, 30, and 60 s, respectively. Brackets were bonded on the teeth in both the groups using SEP and light cure adhesive. The SBS were determined using universal testing machine. The comparison of SBS was done using one-way analysis of variance and Tukey's honest significant difference test.
  
  
  RESULTS
  The SBS of experimental Group 2 was significantly higher than the control Group 1 (p < 0.0001). Further, the SBS of Group 2a was highest, followed by Group 2b and 2c (p < 0.0001).
  
  
  CONCLUSIONS
  It was found that pre-etching for 10 s prior to application of SEP-adhesive system increases the SBS of orthodontic brackets.
authors.affiliation: Department of Orthodontics and Dentofacial Orthopaedics, Rungta college of Dental Sciences and Research, Bhilai, Chhattisgarh, India.
authors.forename: Shaheen
authors.initials: S
authors.lastname: Hamdani
authors.affiliation: Department of Orthodontics and Dentofacial Orthopaedics, Rungta college of Dental Sciences and Research, Bhilai, Chhattisgarh, India.
authors.forename: G
authors.initials: G
authors.lastname: Anita
authors.affiliation: Department of Orthodontics and Dentofacial Orthopaedics, Rungta college of Dental Sciences and Research, Bhilai, Chhattisgarh, India.
authors.forename: Javed
authors.initials: J
authors.lastname: Sodawala
authors.affiliation: Department of Orthodontics and Dentofacial Orthopaedics, Rungta college of Dental Sciences and Research, Bhilai, Chhattisgarh, India.
authors.forename: Sumit
authors.initials: S
authors.lastname: Gandhi
authors.affiliation: Rungta college of Dental Sciences and Research, Bhilai, Chhattisgarh, India.
authors.forename: Sayyed Muhammad
authors.initials: SM
authors.lastname: Ali
mesh_terms: D045662:Dental Etching / Q000379:methods; D003799:Dental Stress Analysis; D006801:Humans; D055115:Light-Curing of Dental Adhesives / Q000379:methods; D016910:Orthodontic Brackets; D010756:Phosphoric Acids / Q000627:therapeutic use*; D055116:Self-Curing of Dental Resins / Q000379:methods*
chemical_list: D010756:Phosphoric Acids; C030242:phosphoric acid