IADR Abstract Archives
Adhesion of Metal Brackets on Provisional Materials: In-Vitro Study.
Objectives: To evaluate the resistance to shear bond strength, (SBS) of metallic brackets bonded to acrylic resin of PMMA and BisGMa using three types of adhesives.
Methods: 120 samples of PMMA resin (Duralay® (D)) and BisGMa (Protemp ™ 3 (P)) were manufactured. 12 groups were established (n = 20), according to provisional material, adhesive and thermocycling (TC). Each group had a sandblasted control that allowed to discard the mechanical effects in the results. Metal brackets were cemented using composite resin (Transbond®XT) (1), urethane methyl methacrylate ( UMM-Triad®Gel) (2), or Cyanoacrylate (3). The immediate and subsequent SBS was measured. The Adhesive Remnant Index (ARI) was evaluated to determine the type of union failure. Statistical analysis: The Kruskal-Wallis test was performed to determine differences between groups, the Mann-Whitney test for intra-group paired comparisons and The Dunn post-hoc test (P <0.05) to compare groups according to type of adhesive failure.
Results: No differences in the SBS were observed between sandblasting and no surface treatment, except for the P3-TC group. According to the type of provisional, P3 had greater SBS than D3; P2 and P2 (control) to D2 and D2 (control), respectively. For the thermocycling treatment, P3-TC had lower SBS compared to P3. Regarding to adhesive: SBS of composite resin and Cyanoacrylate were significantly greater than UMM at 24 hours. Post-thermocycling, P1-TC was superior to P3-TC.
Conclusions: There are differences in the in vitro SBS of cemented brackets over the provisional of BisGMA and PMMA, when using composite resin, UMM and Cyanoacrylate. SBS depends on the provisional material, the TC and sandblasting. Composite resin should be the adhesive of choice, UMM is not recommended.
Methods: 120 samples of PMMA resin (Duralay® (D)) and BisGMa (Protemp ™ 3 (P)) were manufactured. 12 groups were established (n = 20), according to provisional material, adhesive and thermocycling (TC). Each group had a sandblasted control that allowed to discard the mechanical effects in the results. Metal brackets were cemented using composite resin (Transbond®XT) (1), urethane methyl methacrylate ( UMM-Triad®Gel) (2), or Cyanoacrylate (3). The immediate and subsequent SBS was measured. The Adhesive Remnant Index (ARI) was evaluated to determine the type of union failure. Statistical analysis: The Kruskal-Wallis test was performed to determine differences between groups, the Mann-Whitney test for intra-group paired comparisons and The Dunn post-hoc test (P <0.05) to compare groups according to type of adhesive failure.
Results: No differences in the SBS were observed between sandblasting and no surface treatment, except for the P3-TC group. According to the type of provisional, P3 had greater SBS than D3; P2 and P2 (control) to D2 and D2 (control), respectively. For the thermocycling treatment, P3-TC had lower SBS compared to P3. Regarding to adhesive: SBS of composite resin and Cyanoacrylate were significantly greater than UMM at 24 hours. Post-thermocycling, P1-TC was superior to P3-TC.
Conclusions: There are differences in the in vitro SBS of cemented brackets over the provisional of BisGMA and PMMA, when using composite resin, UMM and Cyanoacrylate. SBS depends on the provisional material, the TC and sandblasting. Composite resin should be the adhesive of choice, UMM is not recommended.