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VBATDT ratio on zirconia-substrate bonding
d e n t a l m a t e r i a l s 2 9 S ( 2 0 1 3 ) e1–e96
Available online at www.sciencedirect.com
journal homepage: www.intl.elsevierhealth.com/journals/dema
Abstracts of the Academy of Dental Materials Annual Meeting, 9–12 October 2013 - Vancouver, BC, Canada
Session 1 - Thursday, October 10 1 Effect of MDP/VBATDT ratio on zirconia-substrate bonding A. Aggarwal ∗ , G. De Souza University of Toronto, Toronto, Canada Purpose: Our previous studies evidenced that primers for metal containing MDP (10-methacryloyloxydecyl dihydrogen phosphate) and/or VBATDT (6-(4-vinylbenzyl-n-propyl) amino-1,3,5-triazine-2,4 dithiol) would enhance the bonding to zirconia. The purpose of this study was to optimize the ratio of MDP/VBATDT monomers to maximize bond strength between zirconia and resin cement. Methods and materials: Sintered zirconia (Lava, 3M ESPE) slices, 4.0 mm thick, were cut and roughened up to 600 grit carbide silicon paper. Composite resin (3M ESPE) blocks, 6.0 mm thick, were fabricated and hydrated for 30 days. Seven ratios of MDP and VBATDT primers were developed by the manufacturer (Kuraray Co.): G1: MDP(0.5%)–VBATDT(0.0%); G2: MDP(0.5%)–VBATDT(0.1%); G3: MDP(0.5%)–VBATDT(0.5%); G4: MDP(0.5%)–VBATDT(1.0%); G5: MDP(0.0%)–VBATDT(0.5%); G6: MDP(0.1%)–VBATDT(0.5%); G7: MDP(1.0%)–VBATDT(0.5%); G8: No primer-control. Zirconia surface was coated with two layers of primer, air dried and cemented to composite resin substrates using dual cure resin cement (Clearfil Esthetic Cement EX, Kuraray) under standard pressure. Bonded specimens were stored in water for 48 h. Micro-tensile slabs were obtained by cutting the blocks vertically in two different axes and were micro-tensile tested in an Instron machine (crosshead speed of 0.5 mm/min). Results were evaluated by one-way ANOVA and Tukey HSD (a = 0.05). Mode of failure was evaluated under microscope. Mode of failure was classified as type A (failure at zirconia/cement interface), type B (failure at cement/composite interface) and type C (mixed failure). Representative samples were studied under scanning electron microscope.
0109-5641/$ – see front matter http://dx.doi.org/10.1016/j.dental.2013.08.001
Results: Tukey HSD results evidenced that Group 3 (0.5% MDP/0.5% VBATDT) presented the highest bond strength (15.1 ± 5.7 MPa; p < 0.001). The overall results evidenced that none of the molecules worked by themselves and that a minimum of 0.5% MDP is necessary to achieve reasonable bond strength. Most of the groups presented Type A mode of failure (adhesive at ceramic/cement interface), except for G3 and G7, where there was a higher incidence of Type B (cohesive failure between composite and cement). Conclusion: Increased bond strength to zirconia can be achieved by means of chemical bonding employing MDP and VBATDT in an appropriate ratio. http://dx.doi.org/10.1016/j.dental.2013.08.002 2 Biocompatibility of experimental Ti-30Ta implants with compromised primary stability: Effect of TEA M.C.R. Alves-Rezende ∗ , M.J.Q. Louzada, J.A.G. De Oliveira, A.P.R. Alves-Claro São Paulo State University, São Paulo, Brazil Purpose: Ti-Ta alloys have high potential for dental application due to a good balance between high strength and low modulus. Absence of primary anchoring may occur when dental implants are installed immediately after tooth extraction. Tranexamic acid (TEA) is used to reduce fibrin degradation and can prevent early blood clot breakdown. The aim of this study was to evaluate the biocompatibility of Ti-30Ta implants associated or not with tranexamic acid and installed with compromised primary stability. Methods and materials: Fabricated were 20 implants of titanium ASTM F67 (Grade 4) and 20 implants of Ti-30Ta alloy with dimensions of 2.1 mm × 2.8 mm Ø. They were divided (n = 10) into Group I (Ti machined), Group II (Ti machined/tranexamic acid), Group III (Ti-30Ta alloy) and Group IV (Ti-30Ta/tranexamic acid) and were implanted in tibia (defects with 2.5 mm × 3.2 mm Ø) of 40 male rats (250 g).
Available online at www.sciencedirect.com
journal homepage: www.intl.elsevierhealth.com/journals/dema
Abstracts of the Academy of Dental Materials Annual Meeting, 9–12 October 2013 - Vancouver, BC, Canada
Session 1 - Thursday, October 10 1 Effect of MDP/VBATDT ratio on zirconia-substrate bonding A. Aggarwal ∗ , G. De Souza University of Toronto, Toronto, Canada Purpose: Our previous studies evidenced that primers for metal containing MDP (10-methacryloyloxydecyl dihydrogen phosphate) and/or VBATDT (6-(4-vinylbenzyl-n-propyl) amino-1,3,5-triazine-2,4 dithiol) would enhance the bonding to zirconia. The purpose of this study was to optimize the ratio of MDP/VBATDT monomers to maximize bond strength between zirconia and resin cement. Methods and materials: Sintered zirconia (Lava, 3M ESPE) slices, 4.0 mm thick, were cut and roughened up to 600 grit carbide silicon paper. Composite resin (3M ESPE) blocks, 6.0 mm thick, were fabricated and hydrated for 30 days. Seven ratios of MDP and VBATDT primers were developed by the manufacturer (Kuraray Co.): G1: MDP(0.5%)–VBATDT(0.0%); G2: MDP(0.5%)–VBATDT(0.1%); G3: MDP(0.5%)–VBATDT(0.5%); G4: MDP(0.5%)–VBATDT(1.0%); G5: MDP(0.0%)–VBATDT(0.5%); G6: MDP(0.1%)–VBATDT(0.5%); G7: MDP(1.0%)–VBATDT(0.5%); G8: No primer-control. Zirconia surface was coated with two layers of primer, air dried and cemented to composite resin substrates using dual cure resin cement (Clearfil Esthetic Cement EX, Kuraray) under standard pressure. Bonded specimens were stored in water for 48 h. Micro-tensile slabs were obtained by cutting the blocks vertically in two different axes and were micro-tensile tested in an Instron machine (crosshead speed of 0.5 mm/min). Results were evaluated by one-way ANOVA and Tukey HSD (a = 0.05). Mode of failure was evaluated under microscope. Mode of failure was classified as type A (failure at zirconia/cement interface), type B (failure at cement/composite interface) and type C (mixed failure). Representative samples were studied under scanning electron microscope.
0109-5641/$ – see front matter http://dx.doi.org/10.1016/j.dental.2013.08.001
Results: Tukey HSD results evidenced that Group 3 (0.5% MDP/0.5% VBATDT) presented the highest bond strength (15.1 ± 5.7 MPa; p < 0.001). The overall results evidenced that none of the molecules worked by themselves and that a minimum of 0.5% MDP is necessary to achieve reasonable bond strength. Most of the groups presented Type A mode of failure (adhesive at ceramic/cement interface), except for G3 and G7, where there was a higher incidence of Type B (cohesive failure between composite and cement). Conclusion: Increased bond strength to zirconia can be achieved by means of chemical bonding employing MDP and VBATDT in an appropriate ratio. http://dx.doi.org/10.1016/j.dental.2013.08.002 2 Biocompatibility of experimental Ti-30Ta implants with compromised primary stability: Effect of TEA M.C.R. Alves-Rezende ∗ , M.J.Q. Louzada, J.A.G. De Oliveira, A.P.R. Alves-Claro São Paulo State University, São Paulo, Brazil Purpose: Ti-Ta alloys have high potential for dental application due to a good balance between high strength and low modulus. Absence of primary anchoring may occur when dental implants are installed immediately after tooth extraction. Tranexamic acid (TEA) is used to reduce fibrin degradation and can prevent early blood clot breakdown. The aim of this study was to evaluate the biocompatibility of Ti-30Ta implants associated or not with tranexamic acid and installed with compromised primary stability. Methods and materials: Fabricated were 20 implants of titanium ASTM F67 (Grade 4) and 20 implants of Ti-30Ta alloy with dimensions of 2.1 mm × 2.8 mm Ø. They were divided (n = 10) into Group I (Ti machined), Group II (Ti machined/tranexamic acid), Group III (Ti-30Ta alloy) and Group IV (Ti-30Ta/tranexamic acid) and were implanted in tibia (defects with 2.5 mm × 3.2 mm Ø) of 40 male rats (250 g).