Synonims : Porcelain fuzed to metal crowns and bridges
Metal-ceramic crowns and bridges have broad indications and are the best and most common way of aesthetic and functional restoration of dental defects. They are made from metal alloys and ceramic materials which are pieced together both chemically and mechanically. This is done by applying special enamel and dentine ceramic materials (tooth-coloured porcelain) on metal caps covering the filed tooth stumps. The metal caps can be made of ordinary metal (Cr-Ni alloy) or gold.
Metal-ceramic devices are very aesthetic, and possess biological tolerance, rigidity, strength and durability. With the right design and maintenance, they can withstand over 30 years. This type of crowns and bridges reproduce completely the shape and size of natural teeth, restore the individual characteristics of human teeth when made appropriately, do not irritate and cause gingivitis. In alive teeth they protect the pulp (the tooth nerve) from thermal irritation and prevent the formation of tartar.
They are used widely for dentures when the appearance is a leading issue and are the best choice in terms of price and quality. They are placed over both alive and endodontically treated teeth, for congenital diseases where teeth are missing (hypodontia/ tooth agenesis, inclined or rotated teeth, diastema – distances between the teeth, enamel hypoplasia, etc.). Unlike plastic and metal crowns which are made of plastic, the colour of metal-ceramics is lasting and does not change with the years. Depending on the individual characteristics of the teeth, dental necks can be “painted “, cutting edge, etc. and generally the patient can determine the look of his/her teeth. Fabrication of metal-ceramic devices includes all stages of the work from preparation and planning to final cementation.
The metal model and the model of unpolished porcelain are characteristic for the fabrication of metal-ceramic devices. This is where adjustments of the metal skeleton, the colour and shape of the teeth are done. The only disadvantage of the cermet is the high cost and the fragility of the ceramic materials. Minor breakages of the ceramic can be fixed in the mouth, while with major ones, the device should be removed and the ceramics replaced.
All bridges, including metal-ceramic ones, are used for patients who are over 18 years old where the growth of the jaws is completed. There is no such restrictions with dental crowns. Metal-ceramic material meets all the requirements from a functional and aesthetic point of view and is made for all types of dental defects which require bridge prosthetics. It is difficult to distinguish between natural teeth and prosthetics when the device is properly made. It is only the all ceramic crowns and bridges that surpass the metal-ceramic ones.