Bonding with zirconia

Ceramics has become the material of choice for indirect restorations. Porcelain-on-metal restorations have been successfully used for permanent restorations for 50 years and serve as a benchmark for survival and the success of indirect tooth-colored restorations.

Zirconia restorations are an alternative to ceramic-to-metal restorations due to their strength, biocompatibility and the growing demand for more esthetic restorations. The clinical success of restorations depends on fracture strength, marginal compliance, esthetic outcome and survival. The most common factors affecting marginal integrity are the configuration of the finishing line and the cement gap size, the manufacturing process and cementing.

Zirconia is an extremely strong material with five times the flexural strength of other ceramic materials. Thanks to advances in aesthetics and CAD/CAM technology, zirconia is now used in a wide variety of clinical indications, including single crowns, implants, endodontic posts, and anterior and posterior restorations.

Zirconium oxide bonding can be problematic; Since most bonding protocols are based on bonding to non-zirconia glass, several steps must be followed. Zirconium is a ceramic material, but it is not a ceramic etchant or contains silica. Therefore, the gluing process differs from feldspar porcelain or lithium disilicate. The main problem is that saliva contains a significant amount of phosphate. The saliva contaminates the surface of zirconia restorations and hinders the development of strong bonding due to the depletion of binding sites.

Sandblasting or lightly abrading the particles can be an effective way to improve the bond by creating a new zirconia surface. In addition to decontamination and sandblasting are suitable zirconium oxide primer is also an excellent tool for increasing the bond strength.

Finally, as with any restoration, bond strength is critical to success. That means choosing the right cement or bonding agent. New products, knowledge and technology are making zirconia bonding easier and more predictable than ever, helping clinicians achieve long-lasting and esthetic results.