IADR Abstract Archives
Effect of Surface Pretreatments on the Bond Strength to Zirconia
Objectives: Yttria stabilized tetragonal zirconia polycrystalline is preferred for fixed prostheses due to its high durability. But there is no consensus about a standardized adhesive cementation protocol for bonding zirconia restorations that provide unequivocal and reliable results. The aim of this study was to evaluate the shear bond strength of resin cement to zirconia treated with three different surface treatments and two bonding agents.
Methods: A total of one hundred and sixty zirconia specimens were fabricated from pre-sintered discs (Procera, Nobel Biocare AB) and randomly divided in four groups: Each groups was treated either with a tribochemical silica coating (TSC) (30 µm particle size), hot etching technique using KHF2 crystal slurry for 10 min at a temperature of 280 °C or a solution of 0.5 M NaOH solution with 13.5 pH. No surface treatment groups served as control. After surface treatment an MDP-containing, or a MDP-silane-containing primer was applied to the surface and adhesive resin cement (Panavia F 2.0) was applied. Half of the specimens were stored in deionized water (37°C) for 24 h before shear bond strength (SBS) testing while the other half were thermocycled (5-55°C/5000). SBS test was performed for all specimens. Data were subjected to three-way analysis of variance. Statistical significance was preset at p<0.05.
Results: TSC pretreatment combined with MDP-silane primer group showed significantly higher SBS followed by KHF2 etching groups (p<0.05). Thermocycling resulted in significant reduction in bond strength in all groups (p<0.05) MDP and silane-containing primer showed higher results than only MDP-containing primer for all surface treatments.
Conclusions: Tribochemical silica coating of the zirconia surface combined with a MDP and silane-containing primer improved bond strength immediately and after artificial ageing.
Methods: A total of one hundred and sixty zirconia specimens were fabricated from pre-sintered discs (Procera, Nobel Biocare AB) and randomly divided in four groups: Each groups was treated either with a tribochemical silica coating (TSC) (30 µm particle size), hot etching technique using KHF2 crystal slurry for 10 min at a temperature of 280 °C or a solution of 0.5 M NaOH solution with 13.5 pH. No surface treatment groups served as control. After surface treatment an MDP-containing, or a MDP-silane-containing primer was applied to the surface and adhesive resin cement (Panavia F 2.0) was applied. Half of the specimens were stored in deionized water (37°C) for 24 h before shear bond strength (SBS) testing while the other half were thermocycled (5-55°C/5000). SBS test was performed for all specimens. Data were subjected to three-way analysis of variance. Statistical significance was preset at p<0.05.
Results: TSC pretreatment combined with MDP-silane primer group showed significantly higher SBS followed by KHF2 etching groups (p<0.05). Thermocycling resulted in significant reduction in bond strength in all groups (p<0.05) MDP and silane-containing primer showed higher results than only MDP-containing primer for all surface treatments.
Conclusions: Tribochemical silica coating of the zirconia surface combined with a MDP and silane-containing primer improved bond strength immediately and after artificial ageing.