In vitro analysis of shear bond strength and adhesive remnant index of different metal brackets

Abstract

Introduction: There is a great variety of orthodontic brackets in the Brazilian market, and constantly evaluating them is critical for professionals to know their properties, so as to be able to choose which product best suits their clinical practice. Objectives:To evaluate the bond strength and the adhesive remnant index (ARI) of different brands of metal brackets. Material and Methods:A total of 105 bovine incisors were used, and brackets of different brands were bonded to teeth. Seven different bracket brands were tested (MorelliTM, American OrthodonticsTM, TP OrthodonticsTM, Abzil-3MTM, OrthometricTM, TecnidentTM and UNIDENTM). Twenty-four hours after bonding, shear bond strength test was performed; and after debonding, the ARI was determined by using an optical microscope at a 10-fold increase. Results: Mean shear bond strength values ranged from 3.845 ± 3.997 (MorelliTM) to 9.871 ± 5.106 MPa (TecnidentTM). The majority of the ARI index scores was 0 and 1. Conclusion:Among the evaluated brackets, the one with the lowest mean shear bond strength values was MorelliTM. General evaluation of groups indicated that a greater number of bond failure occurred at the enamel/adhesive interface.

Effect of Yd:YAG laser irradiation on the shear bond strength of orthodontic metal brackets

“…In this sense, it is safe not to damage the dental enamel at the end of the orthodontic treatment. [1][2][3]7,11,14,18,20,21,29 The SBS values of the OPL group (between 29.0 and 63.0 MPa) in present study are in accordance with others authors, 20,25 but results should be viewed with discretion regarding whether bovine teeth could be considered appropriate to substitute human teeth despite their similar structures. Therefore, all results obtained in this in vitro study must be considered just as an estimate to clinical outcomes and should be compared with others researches results performed on bovine teeth.…”

“…High bond strength values are potentially dangerous to enamel and they could cause enamel fracture during debonding. 1,3,7,11,19,20 Although shear bond strength test differs from tensile bond strength, the literature has referenced the potential enamel damage to tensile bond strength as low as 9.7 MPa. 11,26,27 However, authors agree that the values of the SBS obtained in vitro are above the acceptable values in vivo and could carry an increased risk of enamel fracture.…”

“…During orthodontic treatment, bracket adhesion to enamel, through the adhesive system, should be high enough to resist failure [1][2][3] but also permit removal after treatment without causing any enamel damage. 1,2 The failure of the bracket adhesion to the enamel can delay treatment completion, increasing the costs relative to the maintenance of the fixed orthodontic appliances.…”

“…1,[4][5][6][7][8] Previous studies reported that the bond failure of the metal bracket to tooth enamel frequently occurs at the adhesive/bracket base interface. 2,3,5,[8][9][10][11][12] Bracket base design plays an important role in terms of the bond strength to the tooth enamel. 2,[5][6][7]9,13,14 Because metal brackets do not chemically adhere to enamel or resin, studies have been performed to improve the mechanical retention.…”

Priming and bonding metal, ceramic and polycarbonate brackets

“…macroscopically retentive design of the bracket base is therefore of primary importance [57][58][59][60][61][62]. In metal brackets with a mesh base design, larger mesh apertures have been shown to correlate with higher bond strengths, since it allows better resin penetration into the bracket base and allows air to be displaced from under the adhesive [63].…”