Installation of crowns is the most popular type of prosthetics. In appearance, they do not differ from natural teeth and perform their functions. Metal-ceramic crowns are used in modern dentistry. Their advantages, disadvantages and installation are described in the article.
Features
Metal-ceramic crowns are presented as a product made of metal and ceramics. A solid frame is made of metal, having a thickness of 0.3-0.5 mm. Classic types of products are made on the basis of a cob alt- or nickel-chromium alloy. The material has good biocompatibility and strength. If the patient wishes, the alloy is changed to another, created from gold and platinum.
To create metal-ceramic crowns on the front teeth, a gold-palladium alloy is used, since the yellow base makes ceramic coating natural. A ceramic coating is applied to the resulting framework by spraying, completely repeating the natural color of the tooth. Thanks to special technologyproducts are especially durable.
Views
Besides the fact that ceramic-metal crowns are divided according to the metals used in the manufacture of the frame, there is another classification. It is based on the installation method of the structure. Products can be installed:
- to the root of the tooth;
- on implants.
Each type of product has its own advantages and disadvantages. Judging by the reviews, metal-ceramic crowns are reliable for any type of installation.
Roots
This type is used only with partial preservation of the crown part and the presence of a full root. Installation of the structure is carried out in a he althy or completely healed root. For fixation, additional details are used, which are designed to make up for the lost crown part. Applicable 2 types of product:
- Standard pin. It is presented in the form of a cast metal rod, which is implanted into the root to form a tooth stump. It is used for destruction that did not affect the part of the tooth below the gum line. Titanium is usually used in the manufacture, but there are brass, copper, steel pins.
- Stump tab. This is an individual product created in the laboratory. It is used for severe tooth decay, when only the root remains intact. The inlay is made from the same metal that is used in the formation of the crown frame. It is presented in the form of a cast structure, the top of which is formed like a tooth stump, and the bottom repeats the cavity of the root canals.
Before prosthetics, the doctor checks the condition of the oral cavity. Only then is an effective type of treatment prescribed. Metal-ceramic crowns allow you to save the remaining teeth, to prevent their further destruction. The main thing to remember is that after this, oral care should remain of high quality and regular.
On implants
If there are no roots, the installation of crowns is carried out thanks to the implantation of implants. This method is used both in the prosthetics of one tooth, and for complete adentia using a bridge. When installing a ceramic-metal crown on a tooth, preparation of adjacent teeth is not required, since they will not perform supporting functions.
The artificial product is fixed to the abutment, which is similar to a dental stump screwed into the implant. 2 implantation technologies allow to restore teeth:
- Classic (multi-stage). This process is lengthy, usually taking more than 4 months. The specific period is determined by the time of engraftment of the implant. With multi-stage implantation, a titanium root is installed, and then a gum former, and then the crown is fixed.
- Simultaneous. Compared to the classical method, the installation of an implant and fixation of the crown is carried out in 1 procedure. Crowns in this situation will act as a gingiva former.
Mount
Crowns are attached in the following ways:
- Cement. In this situation, the design is fixed on the abutment with a special composite material. For fixing a metal-ceramic crownit will be the best because it has excellent shock absorbing characteristics.
- Screw. With the use of screw fastening, a crown with a hole for screw insertion and a special abutment with a cavity for screwing are used. The hole in the crown is located on the chewing part. Once fixed, the screw platform is covered with a light curing composite.
Indications
According to reviews, metal-ceramic crowns may not always be used. They are effective at:
- missing one or more teeth;
- strong destruction of a noticeable part of the tooth;
- the presence of flaws - chips, cracks, when veneers or composite restoration cannot be used;
- extensive caries lesions;
- high abrasion enamel;
- malposition of teeth;
- wedge-shaped defect;
- fluorosis and severe anomalies in the development of hard tissues of the tooth.
According to experts, prosthetics with a ceramic-metal crown will be an excellent solution in these cases. Updated teeth will not differ from their own. In addition, the person does not feel any discomfort.
Contraindications
These crowns cannot be used for:
- allergies to materials of construction;
- weakness or instability of supporting teeth;
- low crown height of abutment teeth.
Before performing prosthetics, you should consult with your dentist. The specialist will select the appropriate crown option,if there are contraindications to ceramic-metal structures.
Production
How is a ceramic-metal crown made? Impressions are first taken and then sent to the dental laboratory. This is where the product is formed. This is done according to the following instructions:
- A working plaster model is made on the basis of the impression. On its basis, a wax form of the frame is created, from which the product is cast. The metal frame is then fired and sandblasted.
- The resulting frame is treated with an adhesive and ceramics using the jet method. Each layer is oven cured at 980 degrees.
This method provides a strong chemical bond between metal and ceramic, which reduces the risk of chipping during use. Usually the manufacturing process takes no more than 10 days. A properly crafted product can last for many years with proper care.
Installation features
The procedure for installing a ceramic-metal crown is as follows:
- The oral cavity is prepared for the procedure. For this, professional cleaning and dental treatment is performed. If necessary, refilling is carried out. While maintaining the root of the tooth, depulpation is mandatory. With severe tooth decay, a pin or inlay is required.
- Preparation for metal-ceramic crown. Typically, 2 mm of hard tissue is removed during turning. This is needed forto make the artificial product look natural.
- You need to take casts, which are then transferred to the laboratory. Then the dentist installs temporary plastic crowns on a special glue. Many, wanting to save money, refuse them, but after preparation, the teeth are very sensitive, and temporary crowns will be protection from the effects of temperature. They also make the dentition more aesthetic.
- The design is being tried on. When the frame is not treated with ceramics, it is transferred to the fitting room. During this period, flaws are established and the desired color of enamel is selected.
- The resulting product is installed with cement or screw in 1 procedure. Installation of a single crown lasts 15 minutes.
This is how the procedure is performed in all dental clinics. Violation of technology can lead to complications that only a doctor can eliminate.
Benefits
Metal-ceramic crowns are in demand because of their many advantages. They are known:
- Excellent aesthetics.
- Strength.
- Long service life - Porcelain-fused-to-metal crowns last over 15 years.
- Affordable cost.
- Good color and temperature resistance.
- Low chance of chips and cracks.
Ceramic is not erased even with long use. Because of these advantages, many people choose these crowns. It is enough to provide quality care so that they serve for a long time.
Flaws
In addition to the advantages, there are also disadvantages of metal-ceramic crowns:
- During installation, even he althy teeth are turned. This process is considered irreversible. It turns out that to restore one tooth, you need to spoil several he althy ones.
- Depulpation is performed, due to which the tooth becomes dead.
- Frequent allergic reactions to the metal base.
- Cyanosis appears along the edge of the gums.
Although the procedure has its drawbacks, it is still chosen as an effective method of prosthetics. The installation of crowns will improve the condition of the oral cavity.
Care
Recommendations for the care of crowns should be provided by the doctor after they are installed. Usually these are a few rules that will help reduce the risk of oral diseases and extend the life of the prosthesis:
- You need to regularly clean your mouth about bacteria. For this, not only 2-time cleaning with a brush and paste is performed, but also additional devices - dental brushes, floss, irrigator, mono-beam brush. With the help of such tools, it will be possible to eliminate plaque even from hard-to-reach places. During the cleansing period, it is important to pay attention to the gum line and the space between the teeth.
- You need to visit the dentist regularly, because only a specialist can detect a change in the crown or the presence of a pathology of the process at the initial stage.
- Do not allow cleaning with metal objects, chewing hard foods, opening lids with teeth.
Price
CostThe metal-ceramic crown is the main factor that influences the choice of the patient. The price of a structure with a frame made of an alloy of cob alt / nickel and chromium is 6 thousand rubles. But the material of the frame is also taken into account. The cost of a ceramic-metal crown made of a precious alloy is 15,000 rubles. The price is different for all manufacturers. For example, Japanese and European crowns cost 6-8 thousand rubles, while Russian and Belarusian crowns cost 4 thousand.
Probable Complications
The success of prosthetics is determined by the quality of restoration of the anatomical shape of the damaged tooth, which determines the process of chewing food, the correct correction of aesthetics and the preservation of oral he alth. If an error is observed at any stage, the use of a crown can cause complications:
- Violation of the state of the gingival margin. It can be both a decrease in the volume of gum tissue, and thickening, swelling due to inflammation. With the gingival margin, papillae are involved in the process at the site of the placed prosthesis. Such changes appear from poor fit of the edge of the crown to the gum, its constant injury.
- Chronic gingivitis. It is considered an aggravation of the previous complication, it can be detected by the swelling of the soft tissues surrounding the crown, their bleeding. It is necessary to respond in a timely manner to these signs in order not to bring the matter to the destruction of the tooth tissues under the prosthesis. The reason for negative changes is poor-quality prosthetics based on non-compensated preparation or the formation of a model.tooth on an unexamined impression. The only way to fix the problem in this situation is to make a new prosthesis.
If any complications occur, you should consult a doctor. The specialist will examine the problem and prescribe an effective method of treatment. This will prevent negative reactions.
Different from other crowns
Prosthetics of the front teeth can be carried out with metal-ceramic or ceramic products. The first option is recognized as durable and reliable. But in terms of aesthetic properties for the “smile zone”, it is advisable to choose ceramic crowns that are recognized as solid.
Some choose between metal-plastic and cermet. It is advisable to use the second option. Metal-plastic is not very strong and cannot be resistant to mechanical factors. Compared to ceramic, dental resin does not match the natural color of the teeth.
When choosing a frame for the prosthesis of the front teeth, it is desirable to prefer products with zirconium or alloys of expensive metals. The advantage of zirconium is that this substance allows the gum to shine through the shell and create a natural effect.
Many patients note the effectiveness of metal-ceramic crowns. Usually they are recommended to be installed on the back teeth, although updating the front teeth is also allowed. It is important that the work is done by a professional, because then the risk of complications is minimal.
Thus, metal-ceramic crowns are quality products inprosthetics. With proper care and respect, such structures can last for many years.
