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| Cercon providers an innovative system for all ceramics bridges with a maximum of four units. It also offers a new type of CAM technique and optimally co-ordinated components. And of course the system also guarantees reliability as it is based on the long experience, international research and ceramic know-how only Degussa Dental can offer.
Aesthetics and biocompatibility With this high-performance ceramic oxide Degussa Dental meets the wishes and needs of an ever increasing number of modern patients, dentists and dental technicians. Zirconium oxide not only has great strength; it also meets the highest standards of aesthetics and biocompatibility. The framework material Cercon®base and the bonding porselain Cercon®ceram combine to form a single unit almost identical to a natural tooth, with excellent properties, translucency and light dynamics. Accuracy An exceptionally high degree of accuracy can be achieved with Cercon in all ceramic work, both for bridges and crowns, This system allows frameworks for crowns and bridges to be designed with a minimum thickness and inter-proximal spaces, similar to frameworks fabricated using high-strength precious dental alloys. The very slight marginal gaps are comparable to those of metal bonded work. Precisely co-ordinated CAM based technology ensures that the dimensions of the wax pattern are optimally transferred. Strength Zirconium oxide has exceptional qualities making it the first choice for use in the most varied sectors in industry and even in medicine, for example as a reinforced base for artificial hip joints. Zirconiun oxide, for example, automatically sets up a strong resistance to a crack by transforming the microstructural composition of the crystal structure and this enables Cercon base to counteract the expansion of the crack. Zirconium oxide is also unique as a reliable reinforced framework ceramic because it has sufficient strength to withstand the masticatory forces of 800 to 900 Newtons occuring in the posterior region. The use of Cercon will allow all ceramic bridges of up to four units to become standard restorations in dentistry. Keeping essential work in the hands of the technician
Unlike CAD/CAM procedures where the framework is constructed virtually on the computer using the CAD/CAM procedure, the technician waxes up a pattern manually in the normal way with a CAM system using all the pattern materials normally used in precious metal work. The quality of the crown or bridge framework always depends on the quality of the wax pattern. Scanning
The waxed-up pattern is secured in the special frame in the Cercon brain. It is then precisely scanned without contact. The data are digitised and converted by the integrated, computer unit using complex software algorithms.
Milling After the pattern has been scanned, milling commences automatically. The blank, which is also secured in a carrier frame, is milled initially using a rough cutter and then with a fine cutter. The basal and occlusal aspects are milled out of the blank. The rotational and swivel unit of the Cercon brain automatically changes the sides being milled. Additional preparation After milling has been completed, the pattern is removed from the carrier frame. At this stage fine adjustments can nor be completed manually on the chalk-hard material, if required. Sintering
After shaping has been completed, the zirconium oxide framework is thoroughly sintered in the Cercon heat sintering furnace. Shrinkage during sintering reduces the framework to the original size of the precisely fitting wax pattern. This procedure produces all ceramic high strength bridges. Application of the facings (Veneering)
Advanced technology designed to make the work easier, not more complicated Being a system based entirely on CAM, Cercon fits in perfectly with normal laboratory work and specifically uses the dental technician's invaluable know-how. This enables Cercon to guarantee fully customized and consequently perfect prosthetics. Cercon is yur professional partner during the production stages of scanning, milling and sintering: materials, equipment, times and temperatures are synergetically co-ordinated by us and calculations carried out automatically. cercon®brain This is an ideal unit consisting of a laser scanner and milling unit: the class II laser with an output of 1mW scans the conventionally fabricated wax pattern with micro precision. Complex software processes the data and converts it into the milling programme. The special tungsten carbide cutter transposes the dimensions of the wax pattern with the required degree of enlargement calculated in detail for each pattern to the chalk-hard, pre-sintered zirconium oxide Cercon base blanks. The Cercon clean extraction unit extracts the dust produced during milling. cercon®base The Cercon base zirconium oxide blanks are available in all sizes, corresponding to the anatomical size of the crowns or bridges. The material data and batch numbers are read from the barcode on the blanks so that the system always operates according to the respective blanks. The blank can then be clamped very easily into the rotational and swivel unit of the Cercon brain milling unit. cercon®heat At a sintering temperature of 1350°C the milled blanks shrink to the ideal size and strength in approximately 6 hours. During this time zirconium oxide reaches 100% density. The furnace is customised to meet the requirements of the complete Cercon system and is perfectly co-ordinated for each stage of the entire process. Cercon heat has a capacity for all frameworks milled during the day. cercon®ceram With Cercon ceram our very high standard of porcelain quality is now also available in the low-fusing bonding porcelain sector. Cercon ceram has optimal surface quality which aids the development of the gindiva after the restoration has been fitted. It achieves a hardness of approximately 550 HV2 and is optimally matched to the coefficient of thermal expansion of zirconium oxide. Cercon ceram's fracture strength of 90 Mpa is very much higher than the standard requirement of 50 Mpa. A study by the University of Zurich concludes that high-quality bridges must have a solid foundation. A complex challenge Dental restorations should bo of the highest aesthetic quality and biocompatibility. At present all ceramic restorations, for example those fabricated using Cergo injection moulded porcelain, already meet these requirements to a great extent, from facings to inlays and onlays as well as single crowns and small anterior bridges. Compared with precious dental alloys, however, the strength values of porcelain materials used until now were inadequate for long-span bridges. Would high-performance porcelain zirconium oxide prove suitable for long-span bridges in the posterior region? A research team led by Professor Dr. Peter Schärer of the Dental Hospital at the University of Zurich and Professor Dr. Ludwig Gauckler of the Swiss Federal Institute of Technology, Zurich (ETH) took up this challenge with astonishing results. A successful clinical test Posterior bridges with zirconium oxide frameworks could be fabricated and fitted clinically almost from the outset using the DCM (direct ceramic machining) system which was developed by the Swiss Fedaral Institute of Technology, Zurich (ETH) and was the forerunner of the Cercon smart ceramics system. All bridges were subjected to loading by the opposing dentition. After an average observation period of 285 days all bridges were still intact and there were no signs of cracks or porcelain breaking off. The patients were also extremely satisfied |
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