The choice of dentures is now quite large, butwith incomplete tooth decay, dental crowns are the most popular, which allow you to refuse removal. They are made in different ways, from different materials, and sometimes it is difficult to choose a suitable option.
What is a crown and why is it needed?
Crown called the type of non-removable denture.Externally, it repeats the shape of the tooth and when installed it becomes indistinguishable from healthy teeth. It is used in case of incomplete destruction of a tooth in order to restore its chewing functions and aesthetic appearance, as well as to prevent further destruction. Crowns differ depending on the material for their manufacture. They are metal, metal-ceramic, plastic and ceramic. Metal in modern clinics are rarely used, as they have an unaesthetic appearance, and are absolutely not suitable for prosthetic front teeth.
Ceramic have a natural appearance.This is the most expensive type of crowns, they are made of zirconium oxide. Plastic crowns are mainly used as temporary prostheses, since they do not have durability and wear resistance, are easily exposed to mechanical damage and fail. This is the cheapest kind. Metal-ceramic crowns combine beauty and durability, are most popular compared to other species because of their practicality. Dental crowns are also distinguished by the method of manufacture: sometimes a crown is stamped and solid.
Stamped crowns. Principles of manufacture
The production of stamped crowns has already been applied.For more than a hundred years, many dentists consider this process to be a relic of the past, but, nevertheless, it is still used, as it is very cheap. Cylindrical billets of different diameters are made of stainless steel, from which metal crowns are stamped on special machines. Such a product should have some qualities for their proper installation and comfortable wearing.
Коронка штампованная должна подходить четко по the size of the tooth, cover it tightly, without gaps and voids. Otherwise, it will provoke inflammation of the gums, as a result, it can lead to atrophy. For a more tight fit of the crown to the tooth and its fixation using a special dental cement. The crown should not go deep into the gum, it can cause gum disease, for example, periodontitis. In addition, it must conform to the shape of a healthy tooth, so as not to violate the integrity of the series, and be of appropriate size to avoid injury. The product is designed to restore the function of the tooth.
Stages of manufacturing stamped metal crowns
- first, a full impression of the jaw is taken.
- further simulated the desired product
- stamp making
- crown itself is made
- the product is polished and ground
- the finished crown is put on a prepared tooth and fixed with cement.
Indications and contraindications to the use of stamped crowns
Stamped metal crowns use:
- With incomplete destruction of the tooth. In this case, the tooth is grinded to the desired size, all its defects and carious lesions are eliminated in order to prevent further destruction.
- If removable dentures are installed, for example, byugelny, or bridges. To protect the abutment teeth set crowns.
- To restore a broken baby tooth
There are some contraindications to their use:
- Bruxism (teeth grinding, which destroys enamel).
- Complete tooth decay, in which there is nothing left to save.
- Infectious diseases of the oral cavity.
Pros and cons of stamped crowns
Advantages of stamped crowns:
- Tooth preparation does not require much time, turningis carried out at a minimum, as the crown walls are thin. This is especially important if the product is attached to a healthy tooth, which will support the denture.
- This is a medical procedure that allows you to maintain a healthy tooth and avoid removal.
- Crown stamped can be used in thosecases when other types of prosthetics are impossible (for example, the use of implants cannot be made due to diabetes or another patient’s disease).
- This is a cheap method of manufacturing and prosthetics, so it becomes a salvation for people with low incomes.
Disadvantages of stamped crowns:
- Use for a long time leads to abrasion of the crown and its failure. Subsequently, the product will have to be changed to a new one.
- Cement holding the crown over timedissolves, which leads to a loose fit it to the tooth and gum. This, in turn, can lead to damage, formation of caries and tooth decay due to ingestion of food.
- If the tooth is completely destroyed, the crown will not help to perform chewing functions.
- Stamped bridge contains welded parts that shorten its service life.
Solid crowns
The modern method of casting allowed to makehigh-quality thin-walled crowns. A solid crown is used to restore the shape of a damaged tooth, its preservation, as a support for bridges and removable dentures. It is cast from a cobalt-chrome alloy, the result is a solid product without adhesions. Even when creating bridges, soldering of elements is not required, the design is poured out entirely. Such crowns can have various manufacturing options.
- Plain crown without sputtering, polished metal.
- Crown coated gold. May cause allergic reactions. At long wear the dusting is erased.
- Solid plastic crowns. They have a cast metal frame and a plastic lining to impart an aesthetic look to natural teeth. With long or careless wear, chipped plastic is possible.
- Metal ceramics. The most expensive type of crowns, has durability and a natural look.
Indications for use of cast crowns:
- Significant damage to the teeth.
- Pathology forms the teeth or its location.
- Malocclusion.
- Anomaly of the size of the tooth.
- Support for dentures and bridges.
- Prevention of abrasion of teeth, bruxism.
Advantages of cast crowns
- The possibility of solid manufacturing not only individual crowns, but also bridges, which ensures the strength and durability of products.
- Durability. Wearing such crowns can last up to 10 years, if the quality of the material and the installation is performed at a high level.
- Fast and easy manufacturing.
- A solid crown is made individually for each tooth and fits perfectly into the dentition, without causing discomfort in wearing.
- The accuracy of the design allows you to tightly install the crown without gaps, which protects against the ingress of bacteria and food under it.
- For the front teeth, it is possible to produce crowns with dusting or lining for an aesthetic look. Crown stamped does not provide such an opportunity.
Disadvantages of cast crowns
- In preparation for installing the crown, a rather large layer of a healthy tooth is grinded.
- Casting crowns must be ultra-precise, otherwise the installation and wearing will be problematic.
- When taking hot or cold food possible discomfort due to the high thermal conductivity of the material.
- The price of such products is significantly higher than that of stamped crowns.
