ABOUT ZIRCONIUM AND IMPRESSED CROWNS AND BRIDGESIn dentistry, there has been continuous research and development to find materials suitable for dental prosthesis that are aesthetically acceptable and have sufficient strength to withstand the forces of chewing (500-1000lbs pressure on molar teeth) . Besides, they must be well tolerated by the human body. For many years ceramic materials combined with metals have been used in dental restorations – ceramic gives the desired aesthetics and metal is used for strength. Germany now offers a material that has overcome most of the pitfalls of present day products. Patients now have a choice of a material that is esthetic, strong, pure, biocompatible and capable of being used for single and long span dental bridgework. That material is called Zirconium oxide.
The advantages of the All- Ceramic Zirconium Crown & Bridge are:
- Remarkably robust material able to withstand the wear and tear of every day use.
- High crack resistance. If a material is stressed, it may crack. The unusual feature of zirconium oxide ceramic in comparison with other ceramics is that at the appearance of a high-tension area a transformation of the crystal structure can take place and by this volume increase it builds wedges in the crack and therefore it reduces the continuation of the crack.
- Bending strength of over 1000 Mpa which is superior to conventional glass ceramics that show results of 100-200 Mpa and aluminum oxide ceramics lie in the area of 400-600 Mpa.
- Translucency that is very similar to a natural tooth. Light is reflected from a Zirconium crown in much the same way. This means that Zirconium will produce the best aesthetic effect, which is important if your new crowns are to be at the front. It is particularly the case when the crowns will be seen beside natural teeth.
- Fully biocompatible so there are now risks of allergic reactions. It is increasingly being used in general surgery as well as in dentistry.
- No 'black gum line' that can occur with other crowns
- Outstanding marginal fit due to the precision fit of the Zirconium core is derived from computer guided Swiss lathes that cut the form out of a solid Zirconium oxide block. The cutting instructions are obtained from a laser beam that reads 120 points per millimeter from the anatomy of a model of the prepared teeth. Once formed, new synthetic porcelain (99.9% pure) is baked on to the Zirconium core and then shaped like a tooth.
- Less sensitive in the mouth because of the extreme accuracy of the crown fit, the crowns can be cemented with biocompatible dental luting material. This avoids the use of an invasive procedure of etching the tooth with acid and injuring the pulp or nerve of the tooth. This latter procedure often times results in the pulp dying and necessitating root canal therapy.
- Zirconium framework available in 16 Vita shades and it is suitable for full arch bridge restorations.