title: Impact of bracket displacement or rotation during bonding and time of removal of excess adhesive on the bracket-enamel bond strength.
abstract: OBJECTIVE
  This study investigated the the influence of bracket displacement or rotation during fixation and the time of excess adhesive removal from around the bracket on bond strength to enamel.
  
  
  METHODS
  Stainless steel brackets were bonded to the buccal faces of bovine incisors using Transbond XT® adhesive resin. The teeth were divided into five groups (n = 20). In the control group, no displacement or rotation of the bracket was carried out. In the Displac-A group, excess adhesive was removed after the bracket was displaced 2 mm incisally. In the B-Displac group, excess adhesive was removed before the bracket was displaced incisally. In the Rotat-A group, excess adhesive was removed after the bracket was rotated 45°. In the B-Rotat group, excess adhesive was removed before the bracket was rotated. Photoactivation was carried out on the lateral sides of the bracket. A shear test was conducted 10 min after fixation using a knife-edged chisel. Bond strength data were analysed using ANOVA and Fisher's test (5%). The adhesive remnant index (ARI) was scored under magnification. ARI data were analysed using the Kruskal-Wallis test (5%).
  
  
  RESULTS
  No significant differences were detected among the Control, Displac-A, Rotat-A and B-Rotat groups. The B-Displac group showed lower bond strength than all of the other groups, except Displac-A. No significant differences were observed in ARI scores across groups.
  
  
  CONCLUSIONS
  Displacements of the brackets during fixation did not seem to affect the enamel bond strength when excess adhesive is removed after the final positioning of the bracket.
authors: School of Dentistry, Federal University of Pelotas, Rua Gonçalves Chaves 457, 96015-560, Pelotas-RS, Brazil.
authors: Adauê S
authors: AS
authors: Oliveira
authors: School of Dentistry, Federal University of Pelotas, Rua Gonçalves Chaves 457, 96015-560, Pelotas-RS, Brazil.
authors: Caroline K
authors: CK
authors: Barwaldt
authors: School of Dentistry, Federal University of Pelotas, Rua Gonçalves Chaves 457, 96015-560, Pelotas-RS, Brazil.
authors: Luana S
authors: LS
authors: Bublitz
authors: School of Dentistry, Federal University of Pelotas, Rua Gonçalves Chaves 457, 96015-560, Pelotas-RS, Brazil.
authors: Rafael R
authors: RR
authors: Moraes
mesh_terms: D000268:Adhesiveness; D000818:Animals; D002417:Cattle; D002484:Cementation / Q000379:methods*; D003722:Dental Alloys / Q000737:chemistry; D001840:Dental Bonding; D003738:Dental Cements / Q000737:chemistry*; D003743:Dental Enamel / Q000648:ultrastructure*; D003799:Dental Stress Analysis / Q000295:instrumentation; D055115:Light-Curing of Dental Adhesives; D008422:Materials Testing; D009068:Movement; D016910:Orthodontic Brackets; D011897:Random Allocation; D019279:Resin Cements / Q000737:chemistry; D012399:Rotation; D033081:Shear Strength; D013193:Stainless Steel / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties
chemical_list: D003722:Dental Alloys; D003738:Dental Cements; D019279:Resin Cements; C477790:Transbond XT; D013193:Stainless Steel
keywords: Bonding; displacement; excess adhesive; rotation; shear strength