Denture manufacturing materials
(1) Metal materials.
Metal materials are alloyed and pure gold. Alloys such as nickel-chromium alloys, cobalt-chromium alloys, copper alloys, stainless steels, titanium alloys, gold-palladium alloys, and the like. Metal materials are mainly used to make snap rings, support brackets, brackets, etc. of movable dentures, as well as metal crowns and bridges for fixing dentures. Precious metals: Generally speaking, precious metal porcelain refers to the metal crown containing more than 80% gold, and then added with platinum or bismuth, palladium and other elements. It has a higher price, but the advantages are remarkable: after the gold alloy is crowned with porcelain, its luster is close to that of natural teeth, and it has good biocompatibility and safe use; especially the place where the porcelain teeth contact the gums is natural and does not appear green. Black gum edges. Due to the high degree of adhesion, the combination of porcelain and metal is quite firm, and porcelain crown collapse is rare. In China, the use of such precious metal materials is not very common, mainly limited to the higher income class, and has been widely used in developed countries in Europe and America.
(2) Non-precious metals.
Porcelain teeth made of non-precious metals are mostly made of metal inner crowns made of nickel-chromium alloy and high-temperature porcelain. Due to their relatively low price, they are widely used in China. However, this material has certain defects: such as poor edge adhesion; poor biocompatibility with the human body; some patients are prone to black lines in the edge area where the neck and the gum tissue are in contact after wearing for a period of time. Especially in the anterior area, it affects the appearance to a certain extent. At the same time, the coefficient of thermal expansion of the nickel-chromium alloy and the porcelain does not match, so that the phenomenon of collapse of the porcelain occurs. The materials for nickel-chromium alloys are also controversial: it has been reported that nickel-chromium alloys have certain toxic and side effects; others believe that nickel and antimony in nickel-based alloys are toxic to humans, have the potential for sensitization and carcinogenesis; Case reports of the reaction. The side effects of nickel-chromium alloys are usually caused by dental workers often exposed to the particles produced by casting and grinding these metals, which gradually accumulate to cause toxicity and carcinogenesis. Therefore, protection is necessary when processing and manufacturing the castings and clinical operations of such alloys. But the patient is different from the dental mechanic. So far, there are no conclusions and reports on the research of oral cancer induced by nickel-chromium alloy dentures. Among the non-precious metal materials, there is also a new material of pure titanium porcelain teeth, which is characterized by no toxic side effects on the human body and the best biocompatibility, which is also a mature titanium alloy in recent years. technology. Its price is higher in non-precious metal materials, but lower than precious metals. Non-metallic materials Non-metallic materials for making dentures are mainly plastics, composite resins and ceramic materials. Plastic and composite resins can be widely used in the manufacture of crowns and bases (dental pads) for dentures. Ceramic materials are mainly used to make crowns. Porcelain teeth have good wear resistance, but they are not firmly bonded to the trays, easy to fall off, and difficult to modify. Since the late 1980s, with the advent of super-ceramic composite fiber bridge technology, the all-ceramic restoration of the crown (all-ceramic crown) will gradually replace the metal porcelain teeth. The all-ceramic crown can completely avoid metal allergic reactions and has better aesthetic effects, but the disadvantage is that the strength is not enough and the price is very expensive. The above three types of non-metallic materials have their own advantages and disadvantages. Older friends can choose the denture material that suits you according to your own situation and doctor's advice.