Amalgam filling


If a tooth has been affected by caries, the substance softened by the bacteria must be removed. A cavity is created, i.e. a hole in the tooth, which must be filled. The filling serves to prevent a further loss of hard tooth substance and to give the tooth its stability again. Fillings made of amalgam are the standard care of health insurance companies in the posterior tooth area.

Why amalgam?

If the hard tooth substance is destroyed by acids, a restoration by the body’s own restoration is no longer possible because the hard tooth substance is not supplied with blood. The defect must therefore be repaired with a filling. Several materials are available for this purpose.

Amalgam fillings have been used for decades in the posterior tooth region. Amalgam is easy to apply, can be contoured and has a hardness that is necessary in the chewing area. In addition, the material is easy to polish and expands slightly during setting, important for reducing the marginal gap of the filling.

Since amalgam is a good conductor of thermal stimuli, an underfilling must always be placed for insulation. This underfilling consists of cement, which is applied to the bottom of the cavity in a thickness of about 1mm. This is usually the tried and tested phosphate cement.

In the past, amalgam was mixed by rubbing it in a mortar until it had a malleable consistency. Today, the two components are mixed in capsules in an automatic machine to form amalgam. This prevents mercury vapours from being produced and released into the environment.

A disadvantage of the amalgam filling is its silver colour and the possibility of absorbing small amounts of mercury from the filling surface. Because of these disadvantages amalgam fillings are controversially discussed today. On the one hand, there are those who strictly reject amalgam fillings because they fear that the release of traces of mercury could lead to mercury poisoning.

On the other hand, there are the advocates of amalgam fillings, who point to the decades of use without proven symptoms of poisoning. Many scientific studies have not proven any danger to the health of those who wear amalgam fillings. If there is any increased absorption of mercury vapours at all, it is for the dentist and his staff.

But here again, no case of poisoning is known. The only contraindication for an amalgam filling is an allergy. But even this is extremely rare.

The negative attitude towards amalgam fillings is therefore unfounded. However, patients generally do not want amalgam fillings nowadays, because they are unsettled by the amalgam campaign, but also for aesthetic reasons. They want to have tooth-coloured fillings that can also be made with plastic filling materials.

However, they do not have the abrasion resistance of amalgam fillings and long-term experience as with amalgam is not yet available. Studies have proven that there is a connection between an amalgam filling and local reactions on the oral mucosa or gums. As the most common form of rare side effects, these usually manifest themselves in allergic reactions or small discoloured areas on the mucous membrane.

However, no evidence has yet been provided that health problems have occurred. A distinction must be made between amalgam poisoning, amalgam contamination and amalgam allergy. Affected patients tolerate amalgam very poorly even far below the toxic limit.

Side effects of a dental metal can include tiredness/weariness, metallic taste, rashes, migraine, nerve pain, sensitivity disorders, inflammation of the mucous membranes, memory problems or psychological symptoms. In general, if the above mentioned symptoms occur after an amalgam filling, one should consult the dentist in charge of the treatment. An allergy test can be carried out after the findings have been recorded.

Then urine and blood tests are carried out to determine the amount of amalgam present in the body. The amalgam filling is still a good treatment for teeth in the posterior region. It is uncomplicated to use, stable against chewing pressure, durable and has been tried and tested for decades.

In summary, the rejection of amalgam is unfounded and not harmful from a scientific point of view. For aesthetic reasons it is not suitable for the anterior region. If caries reoccurs, the old amalgam fillings must be removed.

This creates amalgam dust, which is mixed with the cooling liquid and sucked out. This sludge is collected and disposed of. Every dentist must have such an amalgam separator on his extraction system and provide proof of its disposal.

Mercury, which makes up a fifty percent share in most dental fillings, is very toxic and is subject to the German Ordinance on Hazardous Substances. For this reason, certain protective measures must be taken by the dentist both when placing a new amalgam filling and when removing it. Mercury from the amalgam filling can enter the body through evaporation, through abrasion of the fillings or through corrosion (= extraction of mercury ions).

Most dangerous is the mercury vapour. This is released especially with heat. For this reason, even the drilling out of old amalgam fillings, where high temperatures hit the filling for a short time, cannot be completely free of stress.

The dangerous thing about the vapours is that they are absorbed by the mucous membranes and the lungs during inhalation and cannot be eliminated afterwards. The absorbed mercury is stored in the nerve cells, blood, tissue fluid and lymph. The mercury content of the amalgam filling, which is released by the years of abrasion of the filling, is low.

If you have a lot of amalgam fillings in the posterior region, you should think about replacing them, especially if they have to be replaced anyway due to new caries. During pregnancy, certain precautions should be taken to protect the unborn child. Especially during dental treatments, the materials used and local anaesthetics used for anaesthesia must be carefully considered.

Many of them can cause health problems for the unborn child. In order to reduce the mercury exposure for the baby to a minimum, one should avoid placing amalgam fillings during pregnancy. Any removal of amalgam should also not be carried out during pregnancy.

If you have already received amalgam fillings before pregnancy, the entire mercury load is harmless to the unborn child, as the fillings are well polished and sealed. The part of mercury that gets into the body through abrasion in the mouth during pregnancy is very small and does not endanger the unborn child. Amalgam is considered a very cheap and durable material for filling teeth.

For this reason, amalgam fillings are the only filling material covered by health insurance companies. But amalgam can be harmful to health. The mercury content already evaporates at room temperature.

Patients with many amalgam fillings can often have their fillings replaced by plastic. Unfortunately, the removal of amalgam fillings cannot be carried out completely without stress. The reason for this is the increased release of mercury vapours.

When drilling out the fillings, very high temperatures act on the filling for a short time. As a result, more dangerous vapours are released. To protect the patient, the dentist should take various protective measures such as a rubber dam (= a kind of rubber blanket that separates the teeth from the oral cavity), low-speed turbines and strong suction systems.

After the amalgam has been removed, the tooth can be restored with plastic fillings, all-ceramic restorations, gold inlays or cement fillings. You can find more information about rubber dams here. An amalgam filling is drilled out during an amalgam restoration.

Low-speed drills are usually used for this purpose. On the one hand, not too high temperatures should be generated in order to keep the mercury vapours low. On the other hand, not too many amalgam splinters should be produced when drilling out the filling.

Furthermore, certain safety measures should be taken by the dentist. These include the application of a rubber dam, special suction cups and low-speed drills. After the amalgam filling has been removed, the cavity (= the hole) can be restored with different materials.

In most cases the choice is a plastic filling. It is calculated per area and must be paid privately. The advantages of plastic are the aesthetics as well as the costs.

The colour of the acrylic can be matched very precisely to the colour of the actual tooth. In terms of price, the plastic filling is much cheaper than the alternatives for a new restoration. These are a gold inlay or an all-ceramic restoration.

These two options are particularly convincing due to their durability and resistance. However, they are much more expensive than an acrylic filling. The cost of an amalgam restoration depends on the size of the filling to be removed.

Depending on the position and size of the tooth and the filling, they can be between 40 – 80 €. Added to this are the costs for the new restoration of the cavity (= hole). Health insurance companies only pay for a composite filling (= a tooth-coloured plastic) if there is an amalgam intolerance.

Otherwise the new fillings have to be paid by the patient himself. In most cases, the choice is made for a composite filling. This is billed according to surface area and can cost between 50 and 350€.

Other possibilities are a gold inlay or an all-ceramic restoration. For these the price range is considerably higher. If desired or necessary, an amalgam poisoning of the body (= amalgam drainage) can be carried out.

If you have swallowed an amalgam filling, there is no need to worry. It will leave the body again naturally after 2 – 3 days. An amalgam filling consists of 50% mercury.

The vapours of mercury are very dangerous for the body. These are released especially during the processing when filling the tooth and when drilling out. In the latter case, the vapours are released due to the high temperatures which briefly hit the fillings through the drill.

To reduce the vapours a little, the dentist should take appropriate protective measures for the patient and himself. However, swallowing a long-standing filling is not dangerous. If you are still worried, you can have the mercury level in your blood measured and, if necessary, have a detox carried out.

However, it is very important to visit a dentist to have the cavity, i.e. the hole, repaired. It is also important to find out what the reason was for the amalgam filling originally falling out. Frequently a caries under the filling is the reason for the loss of adhesion of the filling.

Depending on the age of the amalgam filling, it may happen that after a longer period of time a piece of the amalgam filling breaks out or breaks into larger pieces. Often a part is swallowed. In this case there is no need to worry.

The swallowed part of the amalgam filling will find its way out of the body naturally after 2-3 days. If the amalgam filling is broken, this can already be felt with the tongue. You should visit a dentist immediately.

The old filling must be removed completely. An exposed piece in the filling releases more harmful mercury into the body. After the removal of the old filling, there are various possibilities of restoring the tooth.

In most cases the choice is a plastic filling. Amalgam generally refers to an alloy, i.e. a composition of various metals, in which one component consists of mercury. About half of the amalgam filling in teeth consists of mercury.

This is mixed with the so-called filing. This filing consists of silver, copper, tin and zinc. In the past, copper amalgam (65% mercury and 35% copper) was used, which had to be heated for processing.

You can recognize the amalgam fillings in the mouth by their silver-grey colour. Amalgam is very durable and can be processed very well. It hardens itself after a short time.

It is inexpensive and lasts very long and has therefore been a material for dental fillings for almost 200 years. What is dangerous to the body about amalgam is the mercury vapours that are released when the filling is placed and drilled out. Therefore, the dentist should place a rubber dam (a kind of cloth made of rubber) and thus shield the tooth from the rest of the oral cavity.

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Plastic amalgam fillings are recognizable by their metallic grey-silver colour. Due to their poor aesthetics, they are usually located in the posterior tooth area. However, when laughing or speaking, these areas can also sometimes become visible.

Unfortunately, the grey fillings of the teeth cannot be stained white. In order to get a matching filling in the colour of your own tooth, you have to remove the old amalgam fillings and have them replaced by high-quality plastic fillings using tooth-coloured composite. Amalgam consists of mercury, silver, copper, tin, zinc and indium together.

Due to its components amalgam is not magnetic. In its pure form, cobalt, nickel and iron have magnetic properties. However, these are not present in an amalgam filling.

If you have amalgam fillings in your teeth, there is no reason for concern during an MRT examination. You can also have an MRI with amalgam fillings, as they are not magnetic. There is neither a health risk nor can the result be falsified by the amalgam.

According to patient reports, it is possible that the amalgam fillings heat up. This feels a little strange in the mouth, but there is no reason for concern. Amalgam fillings have been used in dentistry for more than 100 years because they are inexpensive and have a long life span.

It has been proven that amalgam lasts on average for at least 10 years in a patient’s mouth. It is used in the posterior tooth region, because of the particularly high chewing forces. However, many patients report that the fillings last far more than 10 years.

The most common causes of a loss of durability are fractures or chipping. A connection between a tinnitus and an amalgam filling has not been scientifically confirmed. Amalgam in dental fillings could be a possible additive cause for the development of multiple sclerosis (MS).

However, this has not yet been scientifically proven. There is not yet scientific evidence of a causal relationship between Parkinson’s disease and amalgam fillings. It has not been proven that amalgam fillings can lead to depression.

A reduction in symptoms after removal of the filling has been described by those affected, but this is more likely to be psychological in the sense of imagination or wishful thinking. Symptoms of amalgam poisoning include fatigue, severe headaches, metallic taste, pain in hands and feet, reduced muscle strength and hypersensitivity.