Bonding Of Zirconia And Veneering Materials In Dental Resotoration

The main aim of this research is to analysis the bonding properties of yttriumdoped zirconia ceramic core material and different veneering materials in terms ofdifferent surface treatment of zirconia ceramic as well as bonding methods. Three kindof veneering materials are employed in this research, veneering porcelain, lithium glassceramics and novel polymer-ceramic composite dental material. As to the bondingmethods, there are two main connecting materials, fusion glass ceramic and resincement. The purpose of these tests is to summarize a best combination of bondingmethods with different zirconia surface treatments.The results are shown as below. As the veneering porcelain is sintered on zirconiaceramic, the shear strength is29.94MPa when the zirconia ceramic surface is aluminasand blasted. If the zirconia is just polished, the shear strength is21.56MPa, and thebiaxial flexural strength is170.97MPa, which is conforming to the internationalstandard. If the lithium glass ceramic is fusion connected to zirconia ceramic, the shearstrength is36.30MPa when the zirconia ceramic is polished, while it can come up to46.30MPa when the zirconia ceramic is sand blasted. And the biaxial flexural strength is607.98MPa and698.35MPa respectively. If the lithium glass ceramic is adhered to sandblasted zirconia ceramic by resin cement, the shear strength is20.17MPa, and thebiaxial flexural strength is539.46MPa. When the zirconia ceramic is coated with a lowfusion silica glass and afterwards treat it with HF acid and silane coupling agent, theshear strength can reach up to25.43MPa and the biaxial flexural strength is517.02MPa.Self-adhesive resin cement can improve the shear bond strength to some extent. Thenovel polymer-ceramic composites developed by VITA Zahnfabrik and3M Companyare examined in this study. And the results show that their hardness is well matched tonatural enamel. Though the bond strength with zirconia core material is not as high asthe lithium glass ceramic, they are qualified according to ISO10447. And the novelcomposite’s mechanical properties are well developed to satisfied clinical application.