Zirconium Dental Implants
Properties of Zirconia (Zirconium Dental Implants)
Zirconia was discovered in 1789 by the German chemist M. H. Klaproth. However, this “wonder material” possessing outstanding properties was rediscovered only in the last decades. Thus zirconia was introduced into dental medicine in different versions as replacement for metal. This material possesses extraordinary properties such as high bending strength (above 1000 MPa), hardness (1200–1400 Vickers) and Weibull Modulus (10–12). Zirconia is partially stabilized by yttrium, which results in these positive properties.
The bending strength of zirconia is increased further by the addition of aluminium oxide. Zirconia is used for the fabrication of kitchen knives, industrial cutting tools and thermomechanically highly stressed parts in the automotive and aircraft industry. In addition to its great strength, it is highly biocompatible. For this reason zirconia is used in medicine (auditory, finger and hip prostheses) and dental medicine (posts, crown and bridge restorations, zirconium dental implants, implant abutments).
The colour of zirconia similar to teeth and its biotechnical characteristics allow the manufacture of biocompatible, qualitatively high-grade and aesthetic tooth and implant reconstructions. Beside many animal-experimental studies regarding basic suitability of zirconium dental implants the successful implantation of dental Zirconia implants has been documented in a row of clinical studies. Zirconium dental implants are used successfully for over 5 years in an increasing number of clinical cases.
ZrO2 ceramics (Zirconium Dental Implants)
The properties of ZrO2 ceramics depend very strongly upon the chemical composition of the material and the manufacturing process. A distinction is made between fully stabilized ZrO2 (FSZ “fully stabilized zirconia”) and partially stabilized ZrO2 (PSZ “partially stabilized zirconia”). Partial stabilization can be achieved by addition of 3–6% CaO, MgO or Y2O3. According to manufacturing conditions, the cubic, the tretragonal or the monocline modification can be stabilized by these. Partially stabilized ZrO2 has high thermal shock resistance and is therefore also suitable for use as mechanoceramic at high temperature.
The cubic modification of zirconium dioxide can be stabilized from the absolute zero point up to the solidus line by addition of 10–15% CaO, MgO or Y2O3 and the ceramic material can be loaded thermally and mechanically up to a temperature of 2600°. However, because of the lower thermal conductivity and the higher thermal coefficient of expansion, in comparison to partially stabilized ZrO2, the thermal shock resistance of fully stabilized zirconium dioxide is lower. The zirconium dioxide suitable for use in implants has the following composition: 95% ZrO2 + 5% Y2O3. A brilliant smile needs not only white teeth but also attractive, healthy and pink-coloured gums, filling the interdental spaces optimally.
Zirconium Dental Implants (The Z-Look3 implant system)
To facilitate this, Z-Systems has developed the Z-Look3 implant system. The implants made from the high-performance TZP-A BIO-HIP ® zirconium oxide ceramic are extremely similar to the condition of real teeth and tooth roots, they are excellently biologically compatible and are tolerated very well by the gingiva. Careful development, high quality throughout and many years experience stand behind this certified and approved implant system. With all the advantages it offers:
- Free of metals and good bio-compatibility
- Naturally white and aesthetic
- Very good gum regeneration