Dental IndiaAdvantages and disadvantages of Porcelain and gold dental crowns
Gold crowns are made from gold alloyed with many other metals. The actual gold content can range from 90% to as low as 5%. Gold in its pure state is too soft to withstand the rigors of functioning in the mouth. Platinum or palladium are frequently added to harden the gold. There are some disadvantages. Both raise the already high melting point of the alloy. Platinum is expensive, palladium has been outlawed in some countries because it is toxic, and both turn the gold color to silver. Copper is added to restore the gold color, but it has a reddish tint, is toxic, and forms bubbles in the alloy. Silver can be added to get rid of the red color, and zinc is a toxic metal, but it is in small quantities and it will eliminate the air bubbles. The latter metals also reduce the melting temperature.
Crowns replace what is missing from a tooth, and generally cover all of the crown of the tooth, or that part that is exposed to the mouth. A good crown is the same size and shape as the original tooth, unless it was malformed or malaligned, then the final product is better than the original.
Gold crowns are cemented to the teeth, and are not removable by the patient. They are tough, can withstand chewing without breaking, and usually last from 10 to 20 years. Porcelain or plastic can be attached to the esthetic parts of the crowns, and they can look quite life-like. Care is the same as for the natural tooth.
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