The name zirconium is derived from the Arabic word “Zargun,” or golden in color, which is further derived from the Persian words “zar” for gold and “gun” for color. Zirconium is a naturally occurring element with an atomic number of 40 and is a transitional metal found in nature as the mineral Zircon. It is purified to Zirconium, a silver-colored metal that is corrosion-resistant and has properties like titanium. When combined with oxygen, it forms zirconia, a strong and highly biocompatible ceramic. Zirconium was initially discovered in the 18th century.

The German chemist, Martin Heinrich Klaproth (1743-1817), successfully extracted zirconium oxide from Zircon using a transparent gemstone called jacinth as the starting material. Jöns Jakob Berzelius (1779-1848), a Swedish chemist, was the first to isolate metallic zirconium. For the next 150 years, zirconia was considered little more than a curiosity and it was only utilized for making heavy-duty bricks and special glass with a high refraction index.

In 1969 Helmer and Driskell published the first scientific study of the biomedical properties of zirconia. In 1972 Garvie and Nicholson found that alloying zirconia with oxides like calcia, yttria, and magnesia could stabilize the tetragonal modification of zirconia, preventing its transition from tetragonal to the monoclinic phase and producing ceramics with previously unseen crack resistance.

Yttria-stabilized zirconia has been used in orthopedics to manufacture hip and knee joints as an alternative to cobalt-chrome alloy. This biomaterial is sometimes called “cement steel” because its crystalline reticulation changes when force is applied to the surface. Force effectively seals any cracks by causing a volumetric change. Additionally, zirconia supports the growth of blood vessels and bone cells.

The Dental Materials Preceding Zirconia

The increasing emphasis on esthetics in dentistry has been instrumental in the ongoing search for a material with enough strength and longevity to replace metal. The search initially began in the 1960s with the porcelain jacket crown manufactured from feldspathic porcelain, which was later strengthened with an alumina core. This material, however, had a low compressive strength, restricting its use to anterior crowns.

In 1963 the porcelain fused to metal crown (PFM) was developed, and it remained the gold standard for manufacturing crown and bridge restorations for decades. While the PFM is strong, masking the metal substructure has always been a problem; all-ceramic crowns will always look better than a crown with a metal base. One of the main issues with PFMs is that the color of the metal must be masked with opaque before  layering the crown with natural-looking ceramic. The opaque layer blocks the passage of light through the body of the crown, bouncing back and affecting the value, or brightness, of the crown at the thinnest part of the restoration around the gingival margin. Often, a PFM appears slightly grayer in the cervical third, especially if the restoration was fabricated without a porcelain margin. All-ceramic crowns have no such problems, radiating the natural color of the tooth, particularly in thinner sections, resulting in a more esthetically pleasing restoration.

By the 1980s, the first range of glass-ceramics was introduced, the earliest of which was Dicor. Beautiful yet fragile, Dicor was the first glass to be manufactured using the lost wax technique. Its use was confined to anterior teeth.

The 1990s saw the introduction of Cerec, a milling machine that duplicated a resin inlay from a solid block of ceramic. Empress ceramics, In-Ceram and Procera alternatives were also introduced during this time. Procera consisted of a pressed aluminum oxide core, which was sintered under pressure at a high temperature to create a more dense and stronger aluminous oxide core. Veneering porcelain could be added to the core. Before the introduction of these materials, sintered alumina oxide was the strongest non-metal material used for crowns.

Ceramic restorations drastically changed in the 2000s with the introduction of CAD/CAM systems and the utilization of transformation-toughened zirconia.

The Introduction of Zirconia in Dentistry

Unlike earlier forms of all-ceramic restorations, zirconia meets the combined requirements for excellent esthetics and superior strength. It also satisfies the need for an all-ceramic material for patients with a metal allergy. I’s a popular alternative to alumina restorations. Dental applications include:

• Zirconia dental posts
• Zirconia crowns and bridges
• Zirconia dental implants and abutments

Zirconia Dental Posts

Zirconia dental posts offer a more esthetic solution when restoring anterior teeth and where metal posts could result in gray discoloration of the gingival margin. Their use can also eliminate any complications caused by corrosive reactions with the oral environment and surrounding tissues, such as burning, pain, or a metallic taste.

Zirconia Crowns and Bridges

Monolithic zirconia restorations and layered zirconia frameworks provide high flexural strength and good esthetics.

Zirconia Dental Implants and Abutments

Zirconia implants and abutments provide a metal-free solution for patients with metal sensitivities or concerns. Abutments are matched to the color of teeth and exhibit good tissue compatibility and low plaque accumulation.

Zirconia has also been used for orthodontic brackets. Zirconia brackets are cheaper than alumina ceramic brackets but are very opaque, which decreases their esthetic appeal. Zirconia brackets exhibit good frictional characteristics, reduced plaque adhesion, and acceptable bond strengths. However, these characteristics do not offer any significant benefits compared with polycrystalline alumina brackets.

The Future for Zirconia in Dentistry

Zirconia restorations have been used very successfully for years and provide the patient with excellent biocompatibility and mechanical properties. Originally, the very first zirconia restorations were difficult to successfully veneer due to their bone-white color that was hard to mask without adding too much bulk to the restoration. The introduction of newer, colored, and more translucent zirconia materials has mostly solved this problem, and it is now possible to create highly esthetic restorations suitable for anywhere in the mouth. Monolithic zirconia is especially suitable for posterior restorations, where space is limited, and there is minimal occlusal restoration space. It is also suitable for patients with bruxism as polished zirconia is more effective in reducing antagonistic tooth wear. Using computer-aided design and manufacturing provides the clinician with precision-made, well-fitting restorations requiring minimal chair-side adjustment. Currently, the demand for zirconia far exceeds the demand for PFMs, and these older-style restorations are gradually being confined to dental history.

Currently, the most widely used and the strongest and toughest dental glass–ceramics are LD glass–ceramics. This class of glass–ceramic was commercialized for dental framework use and marketed under the trade name IPS Empress 2 in 1998 by Ivoclar Vivadent. However, IPS Empress 2 LD glass–ceramics had high clinical failure rates at 9% to 50% after 24 to 60 months [63], because of the insufficient flexural strength of this material for multiunit prostheses. Subsequently, a new and improved LD glass–ceramic (IPS e.max) with a much higher flexural strength (up to 400 MPa) was launched and the material gained popularity [14,15]. The IPS e.max LD glass–ceramics come in two forms, Press and CAD. IPS e.max Press is processed in the dental laboratory using the well–known lost–wax technique [14]. This technique is distinguished for providing high accuracy of fit.

As mentioned in 4.1, IPS e.max CAD was introduced in 2006 as an LD glass–ceramic, specifically prepared for CAD/CAM soft milling [15]. The material comes prepared in a “blue state,” which permits easier machining and intraoral occlusal adjustment [64]. In the “blue state,” the crystalline phase is lithium metasilicate (Li₂SiO₃) [65]. Once milling has been completed, the restoration is subjected to the second round of heat treatment, in which lithium metasilicate (Li₂SiO₃) reacts with the glass phase (SiO₂) to form LD (Li₂Si₂O₅), which is much stronger and tougher than the Li₂SiO₃. This is the so-called “soft milling,” that effectively reduce the wear of milling tool compared to “hard milling” (direct milling of sintered blocks). Figure 8c demonstrates the typical interlocked microstructure of LD glass–ceramic. The interlocked microstructure produces a high flexural strength that may reach up to 400 MPa and a fracture toughness up to 3 MPa·m^1/2, which allows the use of LD as single restorations anywhere in the mouth and as short–span FDPs in the anterior region [14,44,66]. In addition to their good mechanical strengths, LD glass–ceramics also show advantages over other dental glass–ceramics in terms of adjustable shade and translucency. For instance, IPS e.max CAD is available in the standard A through D shades and also includes a line of bleach shades [44]. The color of the material can be adjusted by the content of the crystalline phase and also by colorant ions dispersed in the matrix. The primary ions consist of V⁴⁺/V³⁺ (blue/yellow), Ce⁴⁺ (yellow), and Mn³⁺ (brown) [15]. Besides, IPS e.max CAD also comes in three levels of translucency, medium opacity (MO), high translucency (HT), and low translucency (LT). This variation is accomplished via adjusting the crystal sizes with HT glass–ceramic exhibiting crystals of 1.5–0.8 mm, whereas LT glass–ceramic exhibits smaller crystals (0.8–0.2 mm) in a higher density [44].

The framework is the foundation of a superior RPD. Ours are designed in accordance with proper bio-mechanic principles and cast with GC® chrome cobalt metal for ease of adjustment and durability.
No quality RPD is complete without top notch acrylic work. It impacts not only esthetics but also the fit and occlusion, That’s why we print the frame first by 3D printer to ensure precise frame fitting .
Additionally, we offer metal-free ( PEEK ) and ( PMM ) RPDs we work it with CAD CAM system although we do not recommend them as a replacement for cast-metal RPDs. We find the processes of adding teeth and making repairs are not as predictable as with conventional RPDs. In our opinion, they should be viewed as long term treatment partials lasting a maximum of 2 years.

After trying the frame comes the acrylic part witch is completely deferent price , We chose a teeth from the local market unless dentist will ask for a deferent teeth sit witch will cost extra for the teeth set price.

Production time will take 15 working days

Additional Resources
For technical questions, assistance in treatment planning a case, or to discuss cases requiring specific handling, please call 00 222 46727777 and ask for TARIQ BADWAN.

ACRYLIC DENTURES & PARTIAL DENTURE

A successful denture is comfortable, functional, durable, and esthetically pleasing from your patient’s perspective. At DENTECH Dental Lab, we dedicate ourselves to delivering those results. Our technicians are experienced and highly educated in various occlusal concepts and theories. We manufacture all of our prosthetics according to specifications using premium base acrylic and denture teeth, Although we use teeth set from the local market unless dentist ask for specific brand.

FLEXITE PARTIAL & DENTURES

To have the best results out of flexile dentures we do use a TCS® I FLEX resin for more transparency and durability , Although this materials we as the first lab in Mauretania to use this material we don’t recommended it for old people nether as a complete denture, As long as the old people they have a sensitive gum and using such material will be hard to take , As we experience working with this material we highly recommend to use it more anterior or as small partial denture as it is more esthetic than older generation acrylic.

Production time will be 1 day for special tray if needed , 1 day for bit rim , 3 days for final try in and 3 days for final delivery

For more information please call TARIQ BADWAN 00 222 46727777