Porcelain crown is a modern dental restoration method. It is a restoration method with precious metal as the supporting core and porcelain outside to achieve the color and function similar to that of real teeth.
At present, there are several kinds of porcelain crowns commonly used in clinic.
1. All-ceramic crown: After grinding a layer (about 1.0- 1.5mm) evenly on each outer surface of the tooth, cover the whole tooth with specially imported all-ceramic materials to restore the shape, function and beauty of the tooth.
Advantages: no metal crown, good aesthetic effect, higher strength than porcelain veneer;
Disadvantages: The amount of tooth tissue removed is relatively large, and because all-ceramic crowns have certain transparency, if the teeth themselves are heavy in color, the internal color will be exposed after wearing them, so this kind of restoration is most suitable for living pulp teeth with large defects or residual roots and crowns restored with dental posts and cores.
Due to the limitation of the strength of the material itself, the above two restoration methods are generally only suitable for anterior teeth. Posterior teeth require high strength and are generally restored with porcelain crowns.
2. Porcelain crown: After a layer (about 1.5-2mm) is evenly worn off the outer surface of the tooth, a special dental porcelain material is sintered on the metal surface at high temperature, so as to restore the shape, strength and beauty of the tooth. Due to the existence of metal inner crown, the mechanical strength is higher than that of porcelain veneer and all-ceramic crown. The disadvantage is that in order to cover the color of the metal inner crown, a layer of shading porcelain is needed. According to the different materials of the inner crown, this kind of porcelain crown is mainly divided into nickel-chromium alloy porcelain crown, titanium-cobalt alloy porcelain crown, gold-platinum alloy porcelain crown and gold deposition porcelain crown.
1) Ni-Cr alloy porcelain crown: the inner crown is made of base metal Ni-Cr alloy. After this kind of porcelain crown is put into teeth, it contains nickel (Ni) metal, and 5% male population and 17% female population will have oral allergic reaction. Even if it is not allergic, in the complex oral environment, the metal parts exposed to the oral cavity will slowly release black oxides, leading to local tissue coloring, which is also the most important reason why this restoration will lead to black lines on the gums. So if your teeth are front teeth, please don't make this porcelain crown in order not to affect your appearance. Its price is low, with regional differences, about 200-500 RMB/capsule.
2) Non-precious metal porcelain crowns are titanium alloy porcelain crowns and gold-plated porcelain crowns. Titanium alloy porcelain crown has outstanding biocompatibility. No metallic odor and no side effects on human body.
The metal has high purity, does not irritate teeth, is not easy to oxidize, and can avoid symptoms such as gingival bleeding and gingival blackening caused by gingival allergy.
High strength, strong combination of porcelain and gold, durable. Domestic titanium alloy porcelain crowns are mainly made of nickel because of their low titanium content (only 4%-6%). The experiment shows that there is no obvious difference in color, edge sealing and gingival gray line between domestic titanium alloy porcelain crown and nickel-chromium alloy porcelain crown.
On the other hand, the gold-plated porcelain crown uses electroplating to transfer precious metals to the surface of non-precious metal castings through electrolyte, forming a gold layer with a thickness of about 0.02mm, wrapping and changing the color of the castings, thus preventing the appearance of gingival gray lines, which has achieved satisfactory results and is worthy of wide application.
Gold-plated porcelain crown has a better effect of preventing gingival gray line than titanium alloy porcelain crown.
Their prices are similar, but there are differences in different regions, about 600-900 RMB/capsule.
3) Gold-platinum alloy porcelain crown and gold-deposited porcelain crown: collectively referred to as precious metal porcelain crown, the inner crowns are gold-platinum alloy and 99.99% electroplated pure gold, which belong to inert metals, so the probability of allergic reaction is small and the physical and chemical properties are very stable. It is worth mentioning that the color of gold-platinum alloy and gold-plated inner crown is close to dentin, so the aesthetic effect of the restoration is better than that of titanium alloy porcelain crown and gold-plated porcelain crown. Their prices are similar, but there are differences in different regions, about 1500-2000 RMB/piece.
Generally, going down twice is enough. 5 days at the earliest and 8 days at the slowest. Then you will achieve your ideal goal.