Crown in one piece: thickness, photo, production steps

In the lateral areas of the oral cavity, a crown is often cast. This is necessary to restore the anatomical integrity of the dentition, when due to various reasons a person loses one or more teeth. This type of prosthetics allows to preserve the functions of the jaw apparatus.

What materials are used to make the crown

Alloys are used for the production of cast crowns, which have high strength. In modern dentistry materials are used based on chromium, additionally doped with nickel, cobalt. Titanium is well proven. This metal has a high resistance to aggressive environment, does not darken, besides it has a high biocompatibility. The crown can be made of solid and precious metals. Gold crowns allow you to make the most accurate fit, as the metal has a high plasticity. They are good in operation, they rarely break. However, the gold crown still wears out, besides it has a high cost. The main indications for prosthetics with solid crowns are the complete loss of one or more teeth, restoration of the functionality of the dentition.

The main types of solid dentures

To date, there are such types of cast crowns:

• Prostheses without sputtering - have the appearance of a parent metal, polished to shine.
• Crown is cast-iron with sputtering (mostly golden). This type also has a disadvantage - sputtering does not have a very favorable effect on the mucous membrane of the oral cavity.
• The third type is crowns with a lining. As a covering material, plastic or cermet is used. Special pads cover the surface of the prosthesis in the smile zone. Despite a good aesthetic appearance, these pads can be cleaved. In addition, their cost is significantly increased due to the use of expensive materials.

The first two types are used to replace the lateral teeth. If the prosthesis of the anterior part of the dentition is necessary, then the third kind is best suited. It should be noted that the crown walls are rather thin (up to 1 mm). This significantly affects the preliminary diameter of the living tooth.

Manufacturing of cast crown. The first clinical and laboratory stages

First of all, the dentist is obliged to inspect the oral cavity. If there are affected areas, they need to be sanitized. The first clinical stage involves obtaining an impression of the dentition and directly the tooth for further casting. To do this, often use a special silicone mass, which allows you to fully display all the anatomical features. During this period, the patient can install special temporary structures. Their task is to accelerate the addiction of gums, create an aesthetic effect. At the first laboratory stage, a demountable gypsum model is manufactured. Next, the gypsum is implanted in the occludator, a wax crown is modeled. After that, the wax is replaced with metal (in a special foundry laboratory). Then the whole-crown is processed properly.

The second clinical and laboratory stage

At the second stage (clinical), the product is stored. In addition, the tooth is grinded for a quality crown installation. The prosthesis is filled with wax, applied to the installation site. Excess material leaves through a pre-drilled hole. Then the crown is removed, all inaccuracies are smoothed, occlusal relationships are checked. The prepared product is transferred to the laboratory. Here, polishing is carried out, polishing. The accuracy of the production is verified on a gypsum model. It is also important to evaluate how the prosthesis is joined with parallel antagonist teeth. It should be noted that the work requires a lot of attention. Even a small discrepancy in size can cause difficulties when wearing a crown, constant pain and discomfort.

Final installation

The crown is fixed in the oral cavity. In this case, the immersion of the end of the prosthesis under the gum should be minimal. The quality of the installation is also checked by the tightness of the patient's tooth. Also, when the antagonists are closed, there should be no discomfort. If necessary, you may need to grind a part of the material. Also, with a lack of material, the crown can be sent back to the laboratory. If the prosthesis is suitable, the person does not feel it, then fixation with permanent cement occurs. It should be noted that if solid crowns are installed, the manufacturing stages take quite a long time - up to several weeks.

The main advantages of these crowns

First of all cast-in crowns have a long service life. Since this technology allows you to fully display all the nuances of the anatomical structure, the prosthesis organically fits into the dentition, food does not get under them, etc. All this allows you to wear them for more than 10 years. In the manufacture of bridges , soldering is not used, and this additionally strengthens the crowns and extends the life of the crowns. Another advantage - under the crown retains more dental tissue (as opposed to cermets). Since the thickness of the whole-crown is less than 0.3-1 mm, the tooth is less subject to grinding. As a consequence, his life is prolonged. In addition, such prostheses are easy to manufacture. Well, of course, the solid crown (the photo below) is more accessible, its cost is relatively low.

Disadvantages of solid constructions

Of course, for the front teeth, such crowns will not work. The minimum choice of color - golden, silver - is one of the significant disadvantages of such prosthetics. The metal has a high thermal conductivity, this can cause unpleasant sensations in the mouth of the patient. Since in the production of hard alloys, crowns can provoke wear, deformation of the dentition of the opposite jaw. In addition, the production of solid crowns requires a high qualification of a specialist.