The development of zirconia ceramic block
Can we find a porcelain with high flexural strength to take place of metal?
A great number of manufacturers exert themselves for this ,and have developed and released some products.However, not only lithium niobate porcelain but also Alumina, the craft and the flexural strength of the material is only suitable to fix one or two teeth.Under this circumstance, the zirconia which has 10000Mpa come into our sight.
There has been no material like zirconia which has profound influence to the development of the dentistry technology. We are very lucky to have the ability to use it. And it seems that all the problems are smoothly solved.Take a look, there are so many teeth connected together, the span is huge. There has been no porcelain material to substitute it and it can rivals the metal. The translucency of the zirconia let the denture get the transmittance of the natural teeth.And the color and texture is lifelike.
The director physician of Eberhard Karls Universität Tübingen, Martin Groten, said in his report that based on the research of German dental ceramic application research team, in the year of 2007, 2.7 million full ceramic denture were made.The practice shows that the zirconia is very suitable for the production of the high intensity prothesis.The quality record shows that the zirconia porcelain has low probability of quality defection. After 10 years’ usage , the fatigue resistance is still pretty high.
As one of the material of porcelain, the zirconia nearly has all the advantages of the porcelain material.And it is used to make ceramic knife for its high strength and solidity.At the same time , as the material to make joint prosthesis, there is no room for doubt that it has high biocompatibility.The combination with the dentistry industry, expand its range in the application of the teeth restoration.However, the high strength (7.5) and high melting temperature（2900℃） brings us a new question:how to process it?
The feature of the zirconia determines that is can not be processed by engraving by hand or by cast.The precision of the teeth restoration and individuality also a problem for the procession.So using the computer numerical control devices maybe is the only solution of the problem.Therefore. from the first day that the zirconia is been used in the dentistry,it is indissolubly bound with the CAD CAM.