Bond Strength and Failure Pattern of Orthodontic Tubes Adhered to a Zirconia Surface Submitted to Different Modes of Application of a Ceramic Primer

Abstract

The aim of this study was to evaluate the shear bond strength of orthodontic tubes adhered to ceramics with the Transbond™ XT bonding resin (3M, Maplewood, MN, USA) while varying the surface treatment. Then, the adhesive remaining index (ARI) was verified, and the representative fracture patterns were evaluated via scanning electron microscopy. Forty-eight zirconia blocks were divided into three groups, varying the number of layers of the 10-methacryloyloxy-decyl dihydrogen phosphate (MDP) primer: one, two, or three applications. In addition, 16 lithium disilicate IPS E.max ceramic disks (Ivoclar Vivadent, Schaan, Liechtenstein) were conditioned with 10% hydrofluoric acid for 20 s and underwent a single-layer primer application regimen. The four groups were further stratified to undergo bond testing after either 24 h (control) or 5000 cycles in a thermocycling machine. A shear bond strength test was performed (0.5 mm/min), and the MPa values obtained were submitted to a two-way analysis of variance and Tukey’s test. There was no statistical difference among the control group ceramics that received the varying surface treatments. After thermocycling, it was verified that both the E.max disks and the zirconia ceramics with three primer applications obtained the highest bond strength values. In the 24 h groups, a total displacement of the resin from the orthodontic tubes was observed (ARI of 1). After thermocycling, the highest prevalence of an ARI of 5 (adhesive failure) was observed among the zirconia ceramics with single-coat primer application, followed by those with triple-coat primer application (mixed failure). Three applications of the MDP-containing ceramic primer achieved the best result in the present study. Zirconia surface should be treated with three coats of MDP primer to achieve a level of bond strength similar to silica-rich phase ceramic.

The Effect of Multiple Applications of Phosphate-Containing Primer on Shear Bond Strength between Zirconia and Resin Composite

“…Based on the results, it was found that one application and two applications of phosphate-containing primer prior to the adhesive agent performed better than adhesive alone. This could be because 10-MDP, a phosphate monomer, was chemically bonded to the outermost surface of zirconia [ 25 ]. A phosphate group at one end of 10-MDP can be chemically bonded to the zirconia’s oxide layer and a double-bonded methacrylate, at the other end, can polymerize with resin composite/cement, resulting in increased bond strength [ 26 ].…”

Orthodontic Attachment Adhesion to Ceramic Surfaces

“…When working on CAD/CAM lithium disilicate, hydrofluoric acid followed by silane shows acceptable SBS values indifferent of adhesive, but slightly higher on roughened surface 56 or MDP adhesive. 57 On feldspathic, leucite based and lithium disilicate samples, testing showed lowest SBS when sandblasting only, feldspathic and lithium disilicate highest SBS with silica coating, leucite based ceramics showed highest SBS values for HF without silane, similar to silica coating. 58 Contradicting these findings, only one study shows that on both feldspathic and lithium disilicate ceramics, lowest SBS was achieved with HF, at a statistically significant difference and highest SBS was achieved when using diamond burs.…”

“…1994 [47] Feldspathic Ceramic Silane/ no silane Sgn difference when silane was used 1999 [40] Amalgam SBS of the silane groups were higher and their microleakage percentages lower than those of the non-pretreated groups [51] IPS e-max CAD Ceramic Polycrystalline with MDP onlylowest values. [57] IPS E-max and zirconia Metallic E-max HF + MDP primer 1 coat; Zirconia MDP 1/2/3 coats Thermocycling E.max and zirconia with 3 MDP primer applications highest SBS [64] Lithium…”

“…18 Three coats of MDP primer showed better results than one coat on zirconia ceramics. 57 When compared to universal adhesive or orthodontic adhesive, MDP showed better results 21 On lithium silicate infused with zirconia, Celtra DUO, SBS was significantly lower than the hydrofluoric acid pre-treated lithium disilicate group. Acid etching may, however, improve adhesion to 2019 [60] Lithium 2019 [21] Zirconia Ceramic MDP ceramic primer + orthodontic primer / universal adhesive / MDP ceramic primer + universal adhesive.…”

Impact of different pretreatments and attachment materials on shear bond strength between monolithic zirconia restorations and metal brackets

“…To date, no gold standard or clinical recommendation exists for conditioning monolithic zirconia restorations when temporary brackets or attachments need to be bonded as part of fixed orthodontic treatment. Although different pretreatment methods have been investigated, most studies focus on the pretreatment methods and include only one attachment material 13 – 16 . Different attachment materials might also have an influence on the bonding strength between bracket and zirconia surface.…”