Why Zirconia Is a Good Choice for Dental Crowns

Zirconium is an extremely durable metal with excellent corrosion-resistance. It finds use in ceramics, abrasives and lamp filaments as well as jet engines and space shuttle parts.

Zirconia can also be used to fabricate dental crowns through CEREC (Chairside Economical Restoration of Esthetic Ceramics), which allows your dentist to craft and install one in just one visit.

Strength

Since the introduction of porcelain-fused-to-metal (PFM) crowns, dentists have searched for materials with both aesthetic appeal and strength to withstand occlusal forces. Zirconia stands out as an option with excellent strength-esthetic characteristics while costing more than other materials such as PFMs.

Zirconia can be improved through various chemical and processing methods. For instance, adding yttrium increases fracture toughness while simultaneously decreasing translucency. Furthermore, this addition also improves ductility and resistance to damage due to cyclic loading-induced phase transformations.

Zirconium metallurgy is an expansive field, and many factors affect its mechanical properties – specifically fatigue behavior and longevity. Fatigue mechanisms may include microcracks and stress concentrations as well as cyclic loading-induced phase transformations; surface modifications also impact fatigue resistance such as grain size, shape and surface finish modifications.

Zirconia is known to outlast other ceramic materials when it comes to durability; therefore various coatings have been developed in order to increase wear resistance and surface chemistry, including titanium nitride, zirconium oxide and tantalum carbide coatings. Zirconia boasts superior wear resistance compared to both alumina and cobalt-chrome alloys.

Studies conducted examining the impact of various conditioning agents combined with two self etch adhesive resin cements (Multilink Speed and Duo-Link universal) on bond strength between zirconia and adhesive resin cements (Multilink Speed and Duo-Link universal). Results demonstrated that when exposed to both of the self etch adhesive resin cements (Multilink Speed and Duo-Link universal), conditioned zirconia framework had greater retention strength with Multilink Speed and Duo-Link universal resin cements than unconditioned zirconia framework due to being exposed to pigmented surfaces which deteriorated bond strength with methacrylate monomers found within these adhesive resin cements.

Durabilité

Zirconia crowns are highly durable, capable of withstanding the intense stress associated with chewing and other occlusal forces, making them an excellent choice for restoring back molars – the teeth which experience the greatest force from these forces in the mouth. Furthermore, zirconia crowns can withstand gum pressure to avoid damage to neighboring teeth while simultaneously preserving dental structures.

Zirconia restorations can be created through digital CAD/CAM workflow, providing full contour single-piece restorations in one go. Unlike PFM which uses layers of porcelain layered and baked over metal framework, monolithic zirconia restorations use one solid material throughout, eliminating bond failure between veneering ceramic and framework.

Traditional powder processing of zirconia involves turning raw zirconia into a dense structure via multiple steps like powder shaping, green machining and sintering. By employing these techniques to transform raw zirconia into solid material structures with precise control of size, shape and homogeneity of material properties resulting in superior mechanical properties and fatigue behavior than that found with porcelain materials.

Zirconia stands out as an exceptional material in that it resists aging. Aging ceramic materials is well-documented as it produces microcracks and stress concentrations which lead to surface degradation and dimension changes; zirconia however is much less vulnerable due to its stiffness, excellent strength/toughness characteristics, and high fatigue resistance.

An additional way to prolong the durability of zirconia is avoiding sandblasting of its framework, as this process is known to cause tetragonal-monoclinic transformation on its surface, leading to microcracks and surface lifts [69]. Furthermore, pigments used for coating zirconia may compete with stabilizing elements at grain boundaries and displace them, leading to poor bonding with veneering ceramic veneering ceramic.

Translucency

Zirconia offers several advantages over older opaque dental ceramics. It allows for more natural tooth colors, enabling gradient creation. Where traditional ceramics require colored stains which wear off over time in an acidic oral environment, transparent zirconia provides natural variations within its construction.

Transparency also aids the zirconia restoration in blending more seamlessly with the patient’s teeth, producing an aesthetic result. Furthermore, translucent zirconia may be surface stained to add additional depth or color. Furthermore, zirconia boasts excellent adhesion to resin cements, making it suitable as an indirect veneer material suitable for resin luting.

Zirconia strength and translucency depend on several factors, including yttria content, particle size, sintering processes and microstructure. Zirconia with higher-yttria contents (3mol%Y) tends to exhibit greater strength but less translucency compared with low-yttria (3-4-5Y-TZP) which has less strength but greater translucency.

Zirconia can also be combined with other materials like glass to further improve its appearance and durability, which is especially popular for anterior restorations where translucent zirconia can be customized to match the tooth shade for the most aesthetic result.

Direct veneers composed of translucent zirconia must be meticulously prepared before the application of adhesive. A rough surface will increase mechanical interlocking and allow for stronger chemical bonds. Many methods have been suggested to prepare zirconia surfaces for resin cement applications, including airborne-particle abrasion (APA), tribo-chemical silica airborne-particle abrasion (TCSAA), plasma spraying, Zr ceramic powder coating application and selective infiltration etching; however, the most reliable approach remains conventional grit blasting technique.

Heat Resistance

Zirconia stands up well under high temperatures while maintaining its structural integrity, unlike traditional refractories like alumina. This property makes it ideal for construction applications in furnaces and kilns as well as replacing metals such as titanium in dental applications due to its heat resistance.

Zirconia stands up well under intense pressure without fracturing or cracking, making it the ideal material for dental restorations requiring the backmost teeth to bear the brunt of biting and chewing pressure, such as crowns and bridges. Other materials often fail under this type of strain too quickly, leading to early failure and costly repair or replacements being needed in due course; but zirconia’s high resistance ensures it provides strength over the course of its lifespan.

Zirconia stands out as an extremely stable ceramic material. Thanks to its resistance against phase changes and thermal shocks, zirconia can withstand high temperatures and thermal shocks that would be detrimental to other ceramic materials. Furthermore, zirconia’s resistance makes it suitable for application sectors requiring the use of refractory materials, such as pistons for high pressure pumps and wear parts.

Construction-grade zirconia is often made using the computer-aided design-and-manufacturing (CAD-CAM) technique, which involves digitally processing and designing restorations through computer software before creating them using various processes such as powder shaping, green machining, sintering and post-processing techniques such as hot isostatic pressing (HIP). HIP treatment helps increase density and durability for greater strength as well as to withstand higher temperatures found in certain application sectors.

Chemical Resistance

Zirconium is highly resistant to corrosion in most mineral acids, strong alkalis and some molten salts. In particular, its resistance to nitric acid makes it suitable for chemical processing environments where other metals would otherwise be vulnerable. Furthermore, Zirconium’s caustic and etchant attacks resistance makes it an excellent choice for construction use in chemical manufacturing operations.

Zirconia’s structural integrity and durability make it ideal for use as an element in nuclear reactors and other complex metal fabrication machinery, where materials must withstand high temperatures, vibration, pressure and welding/machining using standard equipment. Furthermore, its strength, toughness, wear/abrasion resistance and chemical resistance make it suitable as construction material in components like valves pumps piping reactor vessels.

Zirconia’s remarkable properties are fueling advances across multiple scientific fields. From optical devices that amplify and transmit visible/infrared light amplification and transmission to its biocompatibility in medical applications – zirconia shows great promise as an innovator material with significant potential to improve clinical outcomes for dental implant patients.

Researchers have recently demonstrated that zirconia has an extremely low risk of bacterial colonization, helping prevent infections in dental implants and other medical devices. Furthermore, additional research shows it to be biocompatible with bone tissue while having no cytotoxicity effect in soft tissues; these discoveries lay the groundwork for future studies that may lead to improved clinical results using zirconia dental and orthopedic surgery implants in future surgeries. Its strength and biocompatibility could make zirconia suitable for other medical procedures as well.