IADR Abstract Archives
In-vitro Repair of Veneered Zirconia Crowns with Ceramics vs Resins
Objectives: The purpose of this study is to compare load-to-failure (LTF) of veneered zirconia specimens repaired with different materials.
Methods: Zirconia copings (Vita In-Ceram YZ, Vident) were made on standardized metal dies (n=10/group). The copings were veneered with feldspathic porcelain (Vita VM9, Vident) in uniform cylindrical shape (Ø 10.5mm, height 7.5mm). A bevel cut on the porcelain veneer occlusal margin (45degree, 3mm-width) was made to simulate porcelain chipping. The defects were etched with 5% Hydrofluoric acid (IPS Ceramic Etching Gel, Ivoclar Vivadent) and silanated (Monobond Plus, Ivoclar Vivadent) before repaired with 4 different materials: Group A. Conventional resin composite (Tetric EvoCeram, Ivoclar Vivadent) Group B. Flowable resin composite (G-aenial Universal Flo, GC america) Group C. CAD/CAM milled feldspathic ceramic (Vita Trilux Forte, Vident) Group D. CAD/CAM milled lithium disilicate glass-ceramic (IPS e.max CAD, Ivoclar Vivadent). Resin cement (Multilink Automix, Ivoclar Vivadent) was used to cement CAD/CAM ceramic material to the chipped specimens (group C,D). Each specimen underwent 5,000 cycles of thermocycling after repair. The test was performed on Instron universal testing machine by loading vertical force at right angle to the center of the repaired parts with ball-shaped piston at a crosshead speed of 0.5mm/minute. Data were analyzed by ANOVA and Tukey HSD post-hoc tests (α=.05).
Results: Mean LTF (Newton) and SD of repaired veneered zirconia specimens were: Gr.A (660.0±200.5N)a, Gr.B (681.7±175.9N) a, Gr.C (1236.0±188.8N)b, Gr.D (1536.3±286.1N)c. (Letters in superscript indicate significant differences. The most dominant failure mode in all groups was catastrophic failure. Few specimens exhibited cohesive failure. Only one specimen (group D) had adhesive failure.
Conclusions: Veneered zirconia specimens repaired with CAD/CAM ceramic materials exhibited significantly higher LTF than veneered specimens repaired with resin composite (p≤0.05).
Methods: Zirconia copings (Vita In-Ceram YZ, Vident) were made on standardized metal dies (n=10/group). The copings were veneered with feldspathic porcelain (Vita VM9, Vident) in uniform cylindrical shape (Ø 10.5mm, height 7.5mm). A bevel cut on the porcelain veneer occlusal margin (45degree, 3mm-width) was made to simulate porcelain chipping. The defects were etched with 5% Hydrofluoric acid (IPS Ceramic Etching Gel, Ivoclar Vivadent) and silanated (Monobond Plus, Ivoclar Vivadent) before repaired with 4 different materials: Group A. Conventional resin composite (Tetric EvoCeram, Ivoclar Vivadent) Group B. Flowable resin composite (G-aenial Universal Flo, GC america) Group C. CAD/CAM milled feldspathic ceramic (Vita Trilux Forte, Vident) Group D. CAD/CAM milled lithium disilicate glass-ceramic (IPS e.max CAD, Ivoclar Vivadent). Resin cement (Multilink Automix, Ivoclar Vivadent) was used to cement CAD/CAM ceramic material to the chipped specimens (group C,D). Each specimen underwent 5,000 cycles of thermocycling after repair. The test was performed on Instron universal testing machine by loading vertical force at right angle to the center of the repaired parts with ball-shaped piston at a crosshead speed of 0.5mm/minute. Data were analyzed by ANOVA and Tukey HSD post-hoc tests (α=.05).
Results: Mean LTF (Newton) and SD of repaired veneered zirconia specimens were: Gr.A (660.0±200.5N)a, Gr.B (681.7±175.9N) a, Gr.C (1236.0±188.8N)b, Gr.D (1536.3±286.1N)c. (Letters in superscript indicate significant differences. The most dominant failure mode in all groups was catastrophic failure. Few specimens exhibited cohesive failure. Only one specimen (group D) had adhesive failure.
Conclusions: Veneered zirconia specimens repaired with CAD/CAM ceramic materials exhibited significantly higher LTF than veneered specimens repaired with resin composite (p≤0.05).