IADR Abstract Archives
Testing a Novel Technique for Bonding Orthodontic Brackets to Porcelain
Objectives: The objective of this study was to determine if Reliance Assure® Plus provides clinically acceptable shear bonding strength (SBS) for metal orthodontic brackets to CAD/CAM lithium disilicate porcelain restorations.
Methods: Thirty lithium disilicate crowns were milled and divided into two bonding groups: 1) 50µ aluminum oxide microetching and 9.6% hydrofluoric acid (HFA) etch then applying porcelain conditioner and 2) 50µ aluminum oxide microetching, applying porcelain conditioner and Reliance Assure® Plus. The surface morphology of the lithium disilicate was observed after each etching treatment using a scanning electron microscope to characterize the etched surface. Maxillary right central incisor brackets (Ormco™) were bonded with light-cure composite and then stored in artificial saliva for 1 week and thermocycled. The SBS test was performed with an Instron 5566. Adhesive Remnant Index (ARI) scores were obtained to determine the mode of bond failure. Data were analyzed using Independent sample t-tests and an ANOVA test.
Results: For bonding to enamel, Assure Plus protocol gave higher SBS than traditional method (7.29 ± 2.84 MPa vs 5.92 ± 1.23 MPa). Similarly, the SBS of Assure® Plus protocol to porcelain was higher than that of the traditional bonding method (9.42 ± 6.05 MPa vs 6.21 ± 1.50 MPa). However, there was no statistical difference among the SBS results of all groups in this study (p-values >0.05). There was no statistical difference between the ARI results of the lithium disilicate groups (p-values >0.05).
Conclusions: In an in vitro setting, the Assure® Plus bonding technique provides clinically acceptable shear bond strength of orthodontic brackets to lithium disilicate.
Methods: Thirty lithium disilicate crowns were milled and divided into two bonding groups: 1) 50µ aluminum oxide microetching and 9.6% hydrofluoric acid (HFA) etch then applying porcelain conditioner and 2) 50µ aluminum oxide microetching, applying porcelain conditioner and Reliance Assure® Plus. The surface morphology of the lithium disilicate was observed after each etching treatment using a scanning electron microscope to characterize the etched surface. Maxillary right central incisor brackets (Ormco™) were bonded with light-cure composite and then stored in artificial saliva for 1 week and thermocycled. The SBS test was performed with an Instron 5566. Adhesive Remnant Index (ARI) scores were obtained to determine the mode of bond failure. Data were analyzed using Independent sample t-tests and an ANOVA test.
Results: For bonding to enamel, Assure Plus protocol gave higher SBS than traditional method (7.29 ± 2.84 MPa vs 5.92 ± 1.23 MPa). Similarly, the SBS of Assure® Plus protocol to porcelain was higher than that of the traditional bonding method (9.42 ± 6.05 MPa vs 6.21 ± 1.50 MPa). However, there was no statistical difference among the SBS results of all groups in this study (p-values >0.05). There was no statistical difference between the ARI results of the lithium disilicate groups (p-values >0.05).
Conclusions: In an in vitro setting, the Assure® Plus bonding technique provides clinically acceptable shear bond strength of orthodontic brackets to lithium disilicate.