We often divide the porcelain teeth roughly into two kinds: metal ceramic teeth and all-ceramic teeth. Metal ceramic teeth are further divided into non-precious metal ceramic teeth, titanium metal ceramic teeth, and precious metal ceramic teeth.
Non-precious metal ceramic teeth are made by high-temperature porcelain coating on a metal inner crown made of nickel-chromium alloy. Because of its relatively low price, it is widely used in China at present. However, this kind of porcelain tooth has the following disadvantages: poor marginal fit; poor biocompatibility with human body. After wearing for a period of time, some patients will find that the gingival tissue around the neck edge turns "black line". There are even reports of allergic reactions caused by such porcelain teeth abroad. Moreover, due to the mismatch between the thermal expansion coefficient of nickel-chromium alloy and porcelain, chipping of porcelain is more likely to occur clinically.
The inner crown of precious metal porcelain is composed of an alloy of more than 80% gold with platinum or rhodium and other trace elements. Although it is expensive, it has significant advantages: because the golden alloy bottom crown reflects the natural luster of natural teeth under the sunlight, and it has good biocompatibility, so it is safe to use; high tightness; porcelain and metal are well combined, and there are few cases of porcelain chipping. Therefore, it is widely used in Europe and America.
Another worth mentioning is the pure titanium porcelain teeth - this metal porcelain technology has gradually matured in recent years. Titanium is a bio-metal, its greatest feature is that it has no toxic side effects on the human body, and it has the best biocompatibility.
Just because of the high processing difficulty, it was not until recent years that it has been gradually promoted.
All-ceramic teeth, as the name suggests, is a pure ceramic porcelain technology without a metal inner crown. Because there is no restriction of metal, the hierarchy and color of the teeth can be maximized, so the aesthetic effect of all-ceramic teeth is the best; and ceramics are safe and non-irritating to the human body. But due to the influence of porcelain strength, it is currently more used in the fabrication of porcelain veneers, porcelain inlays, and anterior porcelain single crowns.
Generally speaking, the lifespan of a porcelain tooth is about ten years.