title: The effect of air abrasion preparation on the shear bond strength of an orthodontic bracket bonded to enamel.
abstract: The purpose of this study was to determine the method of preparation of enamel which best retains a bonded orthodontic bracket against a shear force. Two hundred and twelve human lower premolars were randomly divided into four equal groups. Group 1 underwent no air abrasion, group 2 received treatment with 25 microm aluminium oxide particles, group 3 with 50 microm particles, and group 4 with 100 microm particles. All groups were treated with a self-etching primer before bonding of an orthodontic bracket. Each tooth was tested in a JJ Lloyd M30K machine to determine the maximum shear force required to dislodge the bracket from the tooth. A one-way analysis of variance test conducted at a 95 percent confidence level (CL) demonstrated that there was a significant difference (P < 0.01) with respect to the four methods of preparation of the enamel surface. An unpaired t-test was then applied at a 95 percent CL. There was no statistically significant difference between groups 1 and 2. There was, however, a statistically significant difference between groups 1 and 3 (P < 0.01), as well as between groups 1 and 4 (P < 0.01). In addition, there was significant difference found between groups 2 and 3 (P < 0.05), groups 2 and 4 (P < 0.01), and groups 3 and 4 (P < 0.05).
authors.affiliation: Department of Preventive Dental Science, University of Manitoba, Winnipeg, Manitoba, Canada. richard_halpern@hotmail.com
authors.forename: Richard M
authors.initials: RM
authors.lastname: Halpern
authors.forename: Tanya
authors.initials: T
authors.lastname: Rouleau
mesh_terms: D020906:Air Abrasion, Dental; D000704:Analysis of Variance; D001840:Dental Bonding; D003743:Dental Enamel; D045662:Dental Etching / Q000379:methods*; D003799:Dental Stress Analysis; D006801:Humans; D016910:Orthodontic Brackets; D019279:Resin Cements; D033081:Shear Strength
chemical_list: D019279:Resin Cements; C429625:Transbond Plus Self-Etching Primer