Chip of a metal-ceramic crown. What to do if a piece of a metal-ceramic crown breaks off

Owners of dentures sometimes face the problem of damage or chipping of the material from the surface of the crowns.

There are many reasons for chips, and many restoration methods.

Description of material

Metal-ceramic crowns are made from an individually made plaster cast and consist of a metal base and a ceramic surface.

The frame can be made of alloys noble metals(gold, silver, palladium) or from base alloys (nickel, chromium, cobalt).

The strength of the structure is ensured by the frame, which fully performs the functions of the lost tooth. And thanks to the ceramic lining, the artificial tooth looks almost the same as a natural one.

To reduce crown fragility, the technology of layer-by-layer application of ceramics is used on outer surface metal, then securely fixed by sintering.

Although metal-ceramic structures are considered strong and durable, it is precisely on such products made from combined materials that chips most often form. This mainly occurs in people who prefer solid foods.

Causes of damage

At the junction of the metal base and the ceramic lining, strong stresses sometimes occur, which can cause chips or other damage to the ceramic.

The main reasons for the formation of ceramic chips include:

• large difference between coefficients of thermal expansion metal and ceramics;
• the intermediate part of the bridge structure is too long(bases made of noble metals have little rigidity, so excessive chewing loads may cause chips on the surface);
• malocclusion, sometimes in combination with pathological grinding of teeth;
• unprofessional tooth preparation(insufficient removal of hard tissues from the chewing surface);
• carrying out large-scale orthopedic work without the use of special equipment;
• using cement that is too thick for fixation metal-ceramic construction;
• entry of foreign bodies between the prepared tooth and the crown;
• poorly executed technical and laboratory work;
• injuries after impact, falls, etc.;
• patient mishandling of artificial teeth(increased loads, temperature changes).

Restorative methods

It is important to know that a broken piece of ceramic should not be thrown away. It must be brought to the doctor, who will determine whether it can be replaced.

There are several ways to solve the problem, namely:

1. Carrying out surface polishing. In this case, the shape of the tooth changes, but, nevertheless, its integrity and aesthetics are preserved. This method is one of the most economical. But it is unacceptable to use it if the teeth are located in the smile zone.
2. Complete replacement of the structure. This is the most reliable method, but it requires a lot of financial costs. It also takes a lot of time to completely replace cermets.
3. Restoration after removal. Since the crown is firmly fixed to the cement, it is very difficult to remove it. Professional skills and special tools are required to avoid damaging the product during removal.
4. Repair without removal. This recovery method is the most popular. All manipulations are carried out directly in the patient’s mouth (the damaged piece is built up using composite materials). The downside of this type of repair is that the crown may not last very long.

If damage occurs as a result of trauma, restoration must be carried out as quickly as possible.

If there is a pronounced fracture line or when complete absence ceramic coating, it is best to re-make the crown.

This type of damage usually occurs after poorly performed technical or laboratory work.

Restoration technique after removal

Repairing metal-ceramic structures is complex and requires strict adherence to technology. In order not to destroy the crown during removal, and to safely fix it in place after restoration, it is necessary to use special tools.

For example, the Coronaflex device allows you to remove the structure using the impact method compressed air. In this case, the crown is not damaged at all, but such a procedure requires large financial costs.

The method of de-cementing a structure using ultrasonic exposure also helps preserve the integrity of the product. But some materials are not susceptible to this effect (for example, glass ionomer cement).

The doctor can use special instruments with which he controls the force of the load on the tissue and the product:

• device with a hook-shaped tip;
• special forceps;
• separating bolt;
• pneumatic hand tools;
• crown removers manual or automatic.

As a rule, the structure is removed under local anesthesia, so the patient does not feel discomfort.

After removal, the dentist gives the product to the dental technician in the laboratory. The restoration procedure for minor damage takes approximately 2-3 hours.

The specialist restores the original appearance of the product by gluing the missing piece using a special composition.

If a fragment is lost, a layer of ceramic is applied to the damaged area, after which the product is dried in a special oven, then sharpened and polished using special equipment.

Repairing the product in the patient's mouth

The restoration procedure is similar to placing a filling. It is important that the crown is dry. Therefore, first of all, the area that needs to be restored is isolated from moisture using a rubber dam.

1. The damaged area is prepared using a diamond bur. This is necessary to create a rough surface and form a bevel, as a result of which the composite material adheres better.
2. The entire surface is cleaned with a brush, after which it is treated with a special acid for a minute. For metal ceramics, only hydrofluoric acid is used. Then the crown is washed with a stream of water, followed by drying.
3. Ceramic surface treated with silane, which dries instantly, and then with a primer.
4. Several layers of opaque material are applied to the damaged area., which covers the metal. Then polymerization is performed with a special lamp for a few seconds.
5. Finally, the specialist coats the area with adhesive., after which, layer-by-layer application of composite materials (dentin, enamel) of the required shade. Each layer is polymerized with a halogen lamp.
6. The last stage is grinding, polishing the surface and removing the rubber dam. After completing all the work, the doctor evaluates the aesthetic result of restoring the metal-ceramic crown.

Composite materials have excellent masking characteristics, therefore, as a result of restoring ceramics using this method, the metal is not visible at all. And thanks to polishing, the tooth acquires a natural appearance.

If the procedure is performed experienced specialist, then any traces of work are completely invisible. The disadvantage of the method is that doctors do not provide guarantees regarding the durability of the crown after restoration.

Forecast

A restored crown can last a year or several years, depending on certain factors:

• damage dimensions(if the chip is too large, the risk of repeated destruction of the crown increases);
• base material(composite materials adhere better to ceramics than to metal);
• malocclusion(in some cases, this factor causes re-formation of the chip);
• improper or poor quality care behind the teeth can lead to damage to the restored crown;
• long bridge structure(due to increased micro bends, damage to the restoration is likely);
• violation of the tightness of the adhesion of ceramics and metal(ceramics may lose their strength over time).

It is important to correctly determine the cause of the chip. For example, if a breakdown occurred due to a violation of the crown manufacturing technology, then it needs to be completely redone. Only by finding out the cause can the recurrence of the defect be avoided.

Price

On average, the cost of restoring a chip on a metal-ceramic crown ranges from 2,500 to 4,500 rubles. Restoration using composite materials will cost approximately 3,000 rubles, with solid inlays - from 4,000 rubles.

Re-polishing the restoration costs approximately 400 rubles, and making a new crown costs more than 10,000 rubles.

First of all, the price depends on the size and location of the damage. Great importance has a specialist qualification. If the chip occurred as a result of an error by the dentist or dental technician, the patient does not pay for the repair.

The video presents a master class on intraoral repair of a prosthesis when the ceramic veneer is chipped.

If a tooth has been seriously damaged due to caries, dentists recommend installing a crown to prevent further destruction. damaged tooth. In the past, to implement such dental procedure steel crowns were used, but they have now been abandoned, giving way undoubted leader– metal ceramics.

Advantages of metal ceramics

In most cases, metal-ceramic structures are available to all clients. The only exceptions are those structures whose frame is made of precious metals. Metal-ceramic crowns are a kind of cap that is placed on a prepared tooth. Crowns are given a shape that completely follows the contours of a real tooth, so sometimes only an experienced dentist can identify an artificial tooth.

Metal-ceramic structures are used both for minor tooth decay and for serious damage. If the root system is excessively damaged, a metal tab is initially installed, and only then all further procedures related to fixing the crown are carried out.

Metal-ceramic structures are accompanied by high strength, reliability, practicality, and wear resistance. In addition, they allow you to restore the aesthetics of the oral cavity. Thanks to the high strength of metal ceramics, the client can eat and chew food as before; the material is able to successfully withstand chewing loads.

But, despite the mass of such excellent advantages, such a design can become unusable due to improper care or circumstances leading to the injury facial area. For this reason, cracks and chips may appear on the metal-ceramic surface; accordingly, you should think about timely repair of the metal-ceramic crown.

A dental clinic providing prosthetics must provide warranty obligations, accompanied for different periods. If it is necessary to repair metal-ceramic crowns within this warranty period, it will be carried out free of charge.

However, each client must understand that warranty repair of a metal-ceramic tooth will be carried out only when all the conditions that were agreed upon when installing the metal-ceramic filling have been met. If specialists identify reasons for which the client himself is to blame, warranty restoration of metal-ceramic teeth will not be carried out.

It should be noted that in most cases, clinics, not wanting to spoil their reputation, leading to the loss of clients, try to fulfill warranty obligations, and therefore carry out restoration of metal-ceramic crowns.

Repair of chipped metal ceramics can be carried out after removal of the prosthesis or directly on it installed in the oral cavity.

The Premier Clinic company carries out restoration of metal ceramics in several ways:

• if the chip is not observed on front tooth, can only polish its edges;
• removal of the metal-ceramic crown, restoration, subsequent installation (in practice, this method is rarely used, since it is very difficult to remove the crown without damaging it);
• creation of a new metal-ceramic crown and its installation.

Restoration is a labor-intensive process, so it is important that each client tries to comply with all requirements to prevent damage to the crowns.

Metal-ceramic structures can perfectly restore functionality and aesthetics in the oral cavity. However, ceramic chipping is not an isolated incident in a doctor’s practice. The reasons are different, as an option: a violation in the preparation of the frame and the technique of working with ceramic mass, parafunction, occlusal overestimation, mechanical impact. In all cases, the patient receives aesthetic dissatisfaction from the appearance of chipped ceramic mass. Repairing chipped ceramics in the oral cavity can sometimes be the only gentle way to restore it.

Aesthetic restoration of chipped ceramics

A 60-year-old patient requested aesthetic restoration of chipped ceramics. (Fig.1)

In the anamnesis, the chip occurred 2 years ago. Several attempts were made to restore the chip classical technique as with restoration with a composite, but they were short-term successful.. She refused the offer to replace the existing prosthesis. I planned to do this later.

IN this moment, she was very interested in the possibility of aesthetic restoration in the oral cavity.

Stages of crown repair

1) Cleaning the surface.

The surface of the prosthesis was cleaned with abrasive pastes on a low-speed tip.

2) A bevel has been made

About 1.5 mm along the surface of the ceramic layer along the periphery of the defect. (Fig.2)

3) Sandblasting

An intraoral sandblaster (Medi-Etcher, Bio-Art) was used to sandblast the surface of the metal frame and ceramic bevel. 50 micron aluminum oxide was used at 2 bar until the surface was rendered matte (approximately 5-8 seconds). (Fig.3)

4) Etching ceramics

The surface was washed with water, dried and hydrofluoric acid 9.5% (Porcelaine etchant 9.5% Bisco) was applied to the ceramic for 2 minutes. (Fig.4)

Ceramics etching is a very important step. By sandblasting and etching ceramics with hydrofluoric acid, we create a micromechanically prepared retention surface. If 4% hydrofluoric acid is used, then it takes 4 minutes to etch the ceramic surface.

5) Wash off hydrofluoric acid from the surface of the crown

At this stage, the ceramic surface becomes very susceptible to contamination. It is necessary to strictly maintain the cleanliness of the ceramic surface from possible organic contamination.
(blood, saliva).

6) Application of ceramic primer

Most important point adhesive preparation of ceramic surfaces. Without it there will be no success.

A ceramic primer is a chemical component with a bimolecular structure. At one end of the chemical chain we have a hydrophobic component (the composite monomer is combined with it); at the other pole we have a hydrophilic component (the ceramic component is combined with it).

I use a two-component primer Bis-Silan (porcelain primer Bis-Silan, Bisco). (Fig.5)

It is better to use a two-component primer. It is more chemically stable than one-component.

When using a one-component primer, carefully monitor the expiration date and store in the refrigerator when not in use.

The ceramic primer is mixed in a dose of 1:1 and applied to the surface of the ceramic (the primer will definitely get on the metal layer, don’t worry) and left for 30 seconds. and evaporates with a stream of air for 5-7 seconds.

7) Next, we apply a composite adhesive to the surface.

In this case, I use One-step plus (Bisco) adhesive; the adhesive is left on the surface for literally 5 seconds. The solvent evaporates and the resin layer becomes thinner.

Polymerization 10 sec.

8) The next stage is the actual recovery.

An important point is priming the metal surface.

In other words, we need to cover the metal layer with a thin layer of opaque material, preferably low-viscosity. Completely block the color of the metal. If we do not achieve this blocking effect, then the metal will shine through through the layer of subsequent composite mass.

In our clinical case I use a flowing opaque (UD, Nanopaq, Schutz Dental) We apply it with an artist’s brush only to the metal layer, we try not to apply it to the ceramic bevel. Otherwise, you will get the opaque mate layer already showing through.
rial.

We achieve uniform distribution of the opaque layer. (Fig. 7)

Next, we add a dentin shade of the corresponding color of the hybrid composite material Aelite All-Purpose Body A2 (Bisco) until the corresponding contour of the tooth is restored (Fig. 8). The hybrid material is quite saturated and ensures the strength of the restoration layer.

We complete the restoration by adding enamel shades of the composite material Aelite Esthetic Enamel A2.(Bisco.)

It is very comfortable to apply and distribute the material with silicone brushes (Kosmetic brush handl #1) using modeling resin from the Tescera set (Tescera / Sculpting-resin, Bisco). Polymerization of the composite layers is carried out according to generally accepted methodology. (Fig. 8)

The surface is processed with diamond burs and finished with faceted burs. (D+Z, Germany) This gives the surface a smooth, cut rather than polished appearance.

At the end of the procedure, the surface is etched with orthophosphoric acid (UNI-ETCH 37%, Bisco), washed, dried and covered with a layer of composite glazing agent Bis-cover. (Bisco) We evaporate the solvent, thin the resin layer and carry out polymerization for 30-40 seconds.

This procedure will bring the shine of the restored surface closer to the shine of the ceramic crown on the adjacent tooth. We obtain a complete aesthetic appearance of the restoration of chipped ceramics. (Fig. 9)

The patient is very pleased with the result.

Conclusions (or why repair ceramics)

Repairing chipped ceramics is a common necessity. It is entirely possible using adhesive working techniques. Key points is: the need to sandblast the surface of ceramics and metal, use ceramic
primer Of course, the longevity of restorations depends on compliance with the adhesive work technique and the elimination of the causes that led to the spalling of the ceramic mass.

Repairing Chipped Ceramics Using the Direct Method. Clinical Case. updated: February 7, 2017 by: Valeria Zelinskaya

Despite the fact that cermets are one of the most durable types of materials, they also require periodic repairs due to the possibility of chips and cracks. Restoration of a chipped metal-ceramic crown, as well as other damage to the structure, is possible today in dental clinics, including in medical center"VTV". Timely seeking help from specialists helps prevent the appearance of micro-wounds in the oral cavity due to friction with sharp chipped crowns and restores normal work jaws.

What is the most common reason for restoration of metal-ceramic crowns?

Chips and cracks form on metal-ceramic crowns even when handled carefully. Among the not so obvious reasons, causing crown breakage, can be distinguished:

• Incorrectly selected and incompatible materials.
• Mistakes made by the dentist when installing crowns.
• Violation of the rules for caring for metal-ceramic prostheses.

Tooth restoration is carried out using high-quality composite materials. Within 20-25 minutes without painful sensations The dentist eliminates traces of breakage of the dentures and, as a result, the artificial teeth look like natural ones again.

How to repair metal-ceramic crowns

We will tell you in more detail about how damaged crowns are restored.

• Restoration of minor damage (photo-hardening composite materials are used to mask small cracks - this requires no more than 30 minutes).
• Repair of large-area damage (first, the metal surface and ceramic coating of the tooth are exposed in the area where the chip is found. The damaged area is treated with a diamond drill and covered layer-by-layer with composite materials; during adhesion, the tooth surface is tightly bonded to it).

In some cases, it becomes impossible to repair crowns, then the dental technician replaces the damaged artificial tooth with a new one. Therefore, it is very important to seek the help of a doctor if cracks are detected at an earlier stage.

Features of caring for metal-ceramic crowns

Repaired crowns must be followed proper care so that the fixed composite material lasts a long time and does not violate the integrity of the entire dentition.

Clean constantly oral cavity and in particular teeth from plaque.

Many people believe that artificial teeth the plaque does not collect, so you can clean off the plaque less often. In fact, bacteria that collect on the surface of the tooth are primarily harmful to the gums. Causing inflammation, plaque can even cause destruction of the supporting tooth. Clean metal-ceramic teeth necessary in the same way as natural ones. It is important to pay attention to the interdental passages - special flosses and brushes are used to care for them.

Visit your dentist regularly

Even if the attending physician has convinced you of the strength of the installed prostheses, it is extremely important to periodically sign up for a preventive examination. This will allow early stages identify small chips and cracks.

Give up bad habits

But even the most attentive patient can harm his metal-ceramic dentures if he continues to adhere to his bad habits: chewing hard objects, his nails, cleaning nuts and seeds with his teeth, or opening bottle caps with them. It is strictly forbidden to clean out food debris from the crevices between teeth using forks or other sharp metal objects.

Dryers and crackers can also harm both repaired and new dentures. Try to consume dry and solid foods as little as possible.

In cases where a bridge is installed, the doctor prescribes washing the prosthesis and gums using a special irrigator or superfloss. It is necessary to use fluoride-containing toothpastes, applying them to the floss.

As a rule, metal-ceramic crowns become unusable precisely because of improper maintenance of the prosthesis. Listen to your doctor's recommendations and then you won't have to pay twice due to your own carelessness.

Restoration of a metal-ceramic crown with damage of any complexity

VTV Medical Center offers restoration services for dental crowns in fast deadlines. We provide complex treatment, dental prosthetics, as well as repairs affordable prices. Individual approach and professionalism of employees, the use of only high-quality materials and modern technologies allows you to achieve a perfect smile and healthy teeth.

VTV managers will tell you about the cost of crown restoration and scheduling a visit to the clinic’s specialists in the form feedback on the website or by phone.

It is quite difficult to damage cermets. But if you set yourself a goal and “make friends” with some solid product, or even metal, then everything is possible. There are several options for repairing cermets:

If the chip occurred on chewing tooth, then you can leave everything as is and, if necessary, polish the sharp edges of the chip. In this case, the tooth is securely covered with a metal frame and will not be destroyed. Or repair crowns. Here is an example - we repair chips in the metal-ceramic crown of a chewing tooth.

The second option is the most reliable, but for this we do not repair the metal ceramics, but completely remake it from scratch.

You can completely remove, repair metal-ceramic crowns and fix them again. But, when removing crowns, there is a high probability of destruction of the teeth and the metal ceramics themselves. Then repairing metal-ceramic teeth will be impossible.

There is a fourth option. Repairing metal-ceramic crowns without removing them. In this case, repair of metal-ceramics occurs using special materials and components that create good adhesion to ceramics and metal. The strength of such crown repairs will be lower than that of conventional ceramics, so after repairing metal ceramics it is better not to overload this area. Repair of metal-ceramic crowns takes about one hour.

An example of cermet repair.

Repair of metal-ceramic anterior teeth.

Repair of metal-ceramic crowns on several teeth at once.

This type of dental crown repair takes about an hour.

Repair of metal-ceramic teeth is possible even with high degree difficulties.

When there is not enough space for material, after repairing chipped metal-ceramic crowns, the metal may be slightly visible. Like in this case.

This is not a repair of metal ceramics, but a repair of a crown with a plastic lining.

After such a metal-ceramic repair, it is not advisable to load the front teeth with hard food.

There is no guarantee for repairs of cermets. But, in the event of a repeated chip in the same area within a year, we will repair it once free of charge.

Good luck to you and your teeth.