IADR Abstract Archives
Influence of universal adhesives on orthodontic brackets bonding to zirconia.
Objectives:
To assess the influence of universal adhesives on bracket bonding to polished or glazed Zirconia blocks for CAD-CAM fabrication of permanent restorations.
Methods:
Six blocks of In-Ceram YZ T monolithic zirconia (VITA, YZ) were used for testing. Three randomly selected blocks were polished (P), while the other ones were glazed (G). Scotchbond Universal Adhesive (3M ESPE, U), Assure Plus (Reliance Orthodontic Products, A), and Transbond XT Primer (3M Unitek, T), all in combination with Transbond XT Paste (3M Unitek), were used to bond 60 brackets. Six experimental groups were thus formed (N=10): 1) P/U; 2) P/A; 3) P/T; 4) G/U; 5) G/A; 6) G/T. Shear bond strength (SBS) and failure mode (Adhesive Remnant Index ARI ) of bonded brackets were assessed.
Results:
SBSs differed significantly among groups (p<0.05). On polished YZ the application of A or U significantly increased SBS in comparison with T (p<0.05). Conversely, no statistically significant differences in bracket retention emerged among glazed YZ specimens, regardless of the adhesive (p>0.05). Glazed YZ treated with A measured significantly lower bond SBSs than polished YZ coated with the same adhesive or with U (p<0.05). Additionally, when using T, significantly higher levels of adhesion were reached on glazed than on polished specimens.
ARI scores differed among groups (p<0.001). A significantly greater amount of resin composite remained on the substrate on polished specimens coated with A or U (p<0.05). When T was used for bonding, failure always occurred adhesively at the composite-substrate interface. The same occurrence was observed in glazed specimens coated with A.
Conclusions:
On polished YZ the SBS values obtained with the universal adhesives largely exceeded those yielded by the control adhesive. On glazed YZ, irrespective of the adhesive, the recorded SBSs were poor and below the threshold of clinical acceptability.
To assess the influence of universal adhesives on bracket bonding to polished or glazed Zirconia blocks for CAD-CAM fabrication of permanent restorations.
Methods:
Six blocks of In-Ceram YZ T monolithic zirconia (VITA, YZ) were used for testing. Three randomly selected blocks were polished (P), while the other ones were glazed (G). Scotchbond Universal Adhesive (3M ESPE, U), Assure Plus (Reliance Orthodontic Products, A), and Transbond XT Primer (3M Unitek, T), all in combination with Transbond XT Paste (3M Unitek), were used to bond 60 brackets. Six experimental groups were thus formed (N=10): 1) P/U; 2) P/A; 3) P/T; 4) G/U; 5) G/A; 6) G/T. Shear bond strength (SBS) and failure mode (Adhesive Remnant Index ARI ) of bonded brackets were assessed.
Results:
SBSs differed significantly among groups (p<0.05). On polished YZ the application of A or U significantly increased SBS in comparison with T (p<0.05). Conversely, no statistically significant differences in bracket retention emerged among glazed YZ specimens, regardless of the adhesive (p>0.05). Glazed YZ treated with A measured significantly lower bond SBSs than polished YZ coated with the same adhesive or with U (p<0.05). Additionally, when using T, significantly higher levels of adhesion were reached on glazed than on polished specimens.
ARI scores differed among groups (p<0.001). A significantly greater amount of resin composite remained on the substrate on polished specimens coated with A or U (p<0.05). When T was used for bonding, failure always occurred adhesively at the composite-substrate interface. The same occurrence was observed in glazed specimens coated with A.
Conclusions:
On polished YZ the SBS values obtained with the universal adhesives largely exceeded those yielded by the control adhesive. On glazed YZ, irrespective of the adhesive, the recorded SBSs were poor and below the threshold of clinical acceptability.