Effects of tooth bleaching on shear bond strength of brackets rebonded with a self-etching adhesive system
- نوع فایل : کتاب
- زبان : انگلیسی
- مؤلف : Ryota Abe · Toshiya Endo · Shohachi Shimooka
- چاپ و سال / کشور: 2010
Description
The purpose of this study was to ascertain the effects of tooth bleaching on the shear bond strength of orthodontic brackets rebonded with a self-etching adhesive system. A total of 39 premolars were collected and divided into three equal groups: in group 1 bracket bonding was performed without bleaching treatment; specimens in group 2 were bonded immediately after bleaching; and group 3 teeth were bleached, then immersed in artifi cial saliva and left for 7 days before bonding. The shear bond strength was measured, with the bonding/debonding procedures repeated once after the fi rst debonding, and the bracket/adhesive failure modes were evaluated by the adhesive remnant index after each debonding. Excepting the mean shear bond strength for group 2 after the fi rst debonding, the overall mean values reached the minimum clinical requirement of 6 MPa. The mean values at the fi rst and second debondings were signifi cantly higher in groups 1 and 3 than in group 2. Between groups 1 and 3, signifi cant differences were noted at the fi rst debonding, but not at the second debonding. Group 2 showed signifi cant differences in mean shear bond strength between the fi rst and second debondings. Bond failure at the enamel–adhesive interface occurred more frequently in group 2 than in groups 1 or 3 after the fi rst debonding. The bracket-rebonding procedure can recover the reduced shear bond strength caused by immediate bonding after bleaching to a clinically acceptable level, but not to the prebleaching level.
Odontology (2011) 99:83–87 DOI 10.1007/s10266-010-0138-z Received: February 1, 2010 / Accepted: May 12, 2010
