It is not always possible to save a tooth from depulping and setting large fillings, which is why many doctors suggest putting a crown. Often, patients panic because they do not always understand what exactly such a product is.
Artificial crown - a cap that completely covers the crown part of the tooth. They are very different and are not always used to restore the shape and function of the tooth. In particular, orthodontic crowns are used to fix devices that correct the dentition.
What are crowns
An artificial crown is used if the tooth is destroyed, broken, discolored or it is not possible to use a filling. With the help of such a device, you can completely restore the chewing function, acquire the aesthetic beauty of a smile, and also prevent the development of a malocclusion.
If it is necessary to install an artificial crown, you need to determine whether it will serve to restore the tooth or actin the form of a support for the installed bridge. The nature of the damage and the features of the dentition are important.
Almost all types of crowns are fixed to the tooth using certain materials, forming a single structure. There is a huge selection of similar products in terms of material, functionality and cost.
What are the types
There are several different types of artificial crowns. Depending on the purpose of these types of prostheses, they are supporting and restorative. Support structures are used for the subsequent fixing of the bridge. Restorative structures are required to eliminate existing hard tissue disorders. Depending on the material used, the artificial crown can be:
- metal;
- non-metallic;
- combined.
Non-metal prostheses are made of plastic or porcelain. Alloys are used for metal, and combined ones are made of metal, which is lined with porcelain or plastic.
Metal crowns are divided into stamped and cast. Such a classification is carried out taking into account the manufacturing method. Cast products are made by casting from metal, according to pre-made molds. Stamped are obtained by stamping from special discs.
Types of products depending on the coverage area
According to the classification of artificial crowns by the area of tooth coverage, there are full and partial. The most popular type is the full design. The choice of product largely depends on the groupteeth to be crowned and how badly damaged they are.
Stump crown is designed to be installed on an almost completely destroyed tooth. This design is characterized by the fact that it is disassembled and reassembled. It can be made from various anti-allergenic materials. The retainer combines the post, the artificial tooth root and the crown itself.
Telescopic crown combines base and outer part. The design fixes removable and non-removable prostheses, as well as certain maxillofacial devices.
Partial crowns are designed to replace the side portions of teeth. It is designed to cover areas affected by caries, and is also used in case of pathological abrasion of teeth. In some cases, it is used in the treatment of various pathologies. A semi-crown covers only half of the tooth and is installed on the front surface of the incisors and front teeth. Caries under an artificial crown is not noticeable and somewhat slows down its development.
Veneer crowns, which are made of plastic or porcelain, are very popular. Sometimes metal-free ceramics are used to make veneers. Unlike all other designs, they are aesthetically pleasing and more attractive.
Species by purpose
Doctors distinguish between several types of artificial crowns according to their purpose. If part of the tooth is missing, then a restorativedesign. Its main purpose is to return the required anatomical shape of the tooth. If most of the teeth are missing in the oral cavity, then this is compensated with the help of prostheses. They require additional support, which is the crowns.
Removable dentures and some types of maxillofacial appliances require contour crowns. The degree of loosening of the teeth at different stages of the course of the disease can be very different. One of the methods of treatment is the use of splinting crowns. They help to remove part of the load from the teeth on the side of the pathology, and slow down the process of their premature loss.
Special healing crowns have a good healing effect. They allow you to somewhat speed up the process of formation of natural dentin. As a result, the hard part of the tooth is restored. This does not require removal of the pulp.
To reduce or prevent pathological abrasion of teeth, prophylactic crowns are installed. They help to slightly change the length of the teeth, as well as restore their attractiveness.
In the process of preparing teeth, the pulp suffers greatly, as various irritants appear on it. Preparation is a preparatory stage for the installation of permanent prostheses. Artificial gum crowns are used to protect the pulp. They help provide better protection.
Varieties by material
Depending on appliedmaterials for artificial crowns, they are divided into metal-composite, metal-free and combined. All-metal are subdivided, in turn, into stamped and solid-cast. Metal stamped types are among the very first that were used to protect natural teeth. However, now they are very rarely used, as they have many disadvantages, among which the following should be highlighted:
- remains of food penetrate into the gum due to the loose fit of the crown;
- short shelf life;
- not very attractive looking.
One-piece cast structures can be of several types, in particular:
- without sputtering;
- sprayed;
- lined with plastic or ceramic.
Solid-cast are made by casting from the metal of the prosthesis. In addition, they may have a golden plating. The advantages of such products include maximum wear resistance, long service life, strength. It is worth noting that they are devoid of the minuses of stamped structures, however, they lack an aesthetic appearance.
For the manufacture of artificial crowns, a combined method can also be used. They are made of metal by casting, but they have one important advantage, since their front surface is covered with a layer of ceramic or white plastic. These materials give crowns fairly good aesthetic qualities.
Properly made cermets are practicallyindistinguishable from natural teeth. The durability of such products is also quite good. It can also be made using shoulder mass. It is a special ceramic that replaces the metal located in the ledge area, which guarantees a stronger fit to the tooth. The crown is more aesthetic. Even if the gum changes its contour a little, then this will not affect the aesthetics at all.
Prostheses made of metal-free ceramics are among the most modern designs and are divided into porcelain and zirconium. Porcelain structures are made by applying high temperature and pressure by injection molding. This technology makes it possible to give ceramics the maximum possible strength, so these crowns do not need reinforcing metal frames at all.
In terms of aesthetic qualities, pressed ceramics are superior to cermets, and they are also more stable. The disadvantages include the possibility of manufacturing only a single prosthesis and their high cost.
Zirconium crowns are made from the most modern materials. They have a more durable frame in natural or white. Similar products are made on the basis of zirconium dioxide, and the coating is made of sintered porcelain. This type of frame is almost as strong as metal, however, it is characterized by light transmission, which makes it possible to imitate the shades of your own teeth as accurately as possible. They are made on an automatic machine.special technology.
Zirconium structures are characterized by maximum accuracy of fit to adjacent teeth. The only drawback of such designs is the high cost.
In some cases, temporary artificial crowns are used. Such products are required to protect the treated tooth from pathogens while the permanent prosthesis is being made. After grinding the tooth and depulping the canal, the threat of infection is very high, so a temporary structure must be installed. In addition to the main function, it also allows you to avoid discomfort while eating and maintain the aesthetics of the oral cavity.
Plastic is also used to make dental crowns. However, it has several drawbacks, so such designs are rarely used. Basically, their aesthetic qualities are quite good, however, after 2-3 years, dark-colored streaks appear on the surface. In addition, it is worth noting that such a product has rather low hygienic qualities.
Now there are new materials made on the basis of photopolymers. It is worth noting that the strength of the plastic is low, and you also have to grind your teeth hard so that the crown does not crack. When in contact with the gum, a plastic crown can cause inflammation and the formation of a dark rim on the gum.
Types by application time
There are various artificial crowns and their types. Their classification largely depends on the time of application. In suchcase, temporary and permanent structures are distinguished. They are selected depending on the problem to be solved. Temporary crowns are made to solve problems such as:
- change in bite height;
- protection of the soft part of the tooth;
- fixing special devices.
Such products are installed for a short period of time, that is, until the installation of permanent structures, and then they are removed. The choice of such products is quite wide and depends on the characteristics of the tooth, which has a certain location. For anterior teeth, PE or polycarbonate products are suitable. For chewing teeth, crowns made of special medical alloys are used. Temporary structures are installed on a special fixing agent and can be easily removed when needed.
Permanent crowns can be of several types, which vary in quality and cost. The material used is mainly plastic, composites, ceramics. For example, ceramic products are suitable for people prone to allergies. They differ in that they do not provoke gum irritation and look as natural as possible.
For the manufacture of metal structures, steel, cob alt, gold, chromium are used. Such products are characterized by the fact that they combine aesthetic appeal, durability and affordable cost. To make your teeth look as natural as possible, it is best to choose gold-based alloys.
How to choose the right one
If there are indications for installationsuch structures, it is necessary to take into account the requirements for artificial crowns. It is recommended to install microprostheses on the front teeth, which have very good aesthetic qualities. These include porcelain or ceramic-metal prostheses.
If you need to install crowns on chewing teeth, it is best to choose cast metal structures. They have an affordable cost, as their aesthetic qualities are not high enough. But such designs have a longer service life.
If you want each chewing tooth to look as natural as possible, then you can use ceramic-metal structures. Products lined with ceramic mass have optimal aesthetic qualities. In addition, it is worth noting that they have a high level of durability.
It is worth noting that it is imperative to take into account the basic requirements for artificial crowns, as it is important to ensure proper care so that they last for a long time. If a ceramic type of construction is installed, then toothpaste, floss and brush will suffice. You can also purchase special irrigators, which are characterized by the fact that a jet of water is supplied through a special nozzle.
Indications for installation
Prosthetics with artificial crowns is widely used, especially since many new and modern materials have recently appeared. However, it is very important to choose the right dentist whowill help you decide which designs are best suited in accordance with all requirements.
It is worth noting that crowns are not installed at the request of the patient, as there must be certain indications for this. Most existing dental problems can be easily fixed with fillings or veneers. Among the main indications for artificial crowns, it is necessary to highlight the following:
- need to fix orthopedic and maxillofacial appliances;
- carious lesions of hard tissues;
- lack of possibility to restore the tooth wall with artificial restoration;
- chewing dysfunction;
- anomalies in the shape of the dentition;
- strong abrasion of the enamel;
- need to increase the height of the lower dentition;
- strong destruction of the crown part of the tooth.
When using artificial crowns, the indications and contraindications of their use must be considered first of all in order to prevent complications.
Contraindications
There are certain contraindications to artificial crowns, among which it is necessary to highlight such as:
- malocclusion;
- small height of the preserved tooth;
- patient age under 16;
- thinning of the front walls of the teeth;
- loose tooth.
In addition, contraindications include the presence of an allergy to the materials used, as well as the presence of certain diseases of the oral cavity.
Key Benefits
There ismany advantages of using an artificial crown, among which it is necessary to highlight such as:
- good aesthetic factors;
- long service life;
- affordable price;
- no need to sharpen your teeth;
- biological compatibility of materials with dental tissues and gums.
The crown installed on the affected tooth will significantly extend its service life and functionality. The ceramic coating is resistant to pathogens that cause cavities.
What could be the disadvantages
It is worth noting that the use of artificial crowns has certain disadvantages, which include such as:
- depulping can lead to inflammation;
- insufficient strength of some types of crowns;
- poor aesthetics of metal products.
In addition, among the shortcomings, it is necessary to highlight the fact that in some cases it will be necessary to injure he althy teeth if they serve as a support. Metal-ceramic requires preliminary grinding of a large volume of fabrics, approximately to a depth of 2 mm on all sides. That is why it is preferable to install veneers on the front teeth.
Since a significant amount of tooth tissue is removed during the grinding process, the pulp is damaged. However, when it dies, the inflammatory process does not develop immediately, but some time after the installation of the crowns. As a result, it may be necessary to remove the crown and then retreat the tooth, and then prosthetics. To avoid the occurrence of such a complication, the teeth are initially depulped, and then the root canals are sealed.
Features of manufacturing and installation
The process of treating a tooth and installing artificial crowns is divided into several stages. If necessary, the tooth is first treated, and then it is prepared so that it acquires the correct shape. The depth of grinding largely depends on the characteristics of the tooth and the type of crown.
After that, the doctor takes casts. According to them, artificial crowns are made in the dental laboratory. While the fabrication process is in progress, a temporary structure is placed on the tooth to prevent damage.
Production of metal-ceramic crowns refers to a rather long and laborious process, since it is necessary to display all the natural features of the tooth. The ceramic mass is applied in layers, as it is necessary to fire each layer in a special vacuum furnace 6-8 times.
When the permanent crown is ready, it is tried on, and if necessary, the shape is corrected. The last step is to fix the artificial crown in its permanent place with cement. Modern dentistry distinguishes several ways of installation and fixation.
The most common option is to install on a pin. This solution has a lot of advantages becauseprovides the required level of reliability and durability, and also has an affordable price. The pin is a rod made of plastic or metal. It is installed in the tooth socket and fixed with special materials.
A prerequisite for this method of fixing an artificial crown is the presence of a completely he althy root, which must also have the appropriate size. Another installation method is the use of a stump tab. Before performing such a procedure, a tooth filling is performed.
If it was not possible to save the tooth root, which can act as the basis for prosthetics, then prosthetics with implantation are used. This process is longer, but the result is a completely he althy tooth.
