Amalgam restoration (grey filling)
Definition
Dental amalgam is an alloy composed mainly of mercury, silver, copper and tin. Very resistant, it is used to restore a broken, cracked or fractured tooth, or one affected by tooth decay.
Dental amalgam is very old, so it is part of the first generation of filling materials in dentistry. In 1896, the formula used was improved, but it has remained virtually unchanged since the 1960s.
- Prevent the spread of dental caries;
- Reduce the possibility of infection, especially of the gums;
- Prevent the recurrence of dental caries;
- Ensure the functionality of the restored tooth.
Advantages
- As amalgam is a restorative material that resists high pressure, it is ideal for cavities on the posterior teeth;
- The high sealing power of the amalgam ensures a good seal for teeth whose risk of recurrence is high given their position;
- The durability of dental amalgam is higher than that of composite resins;
- Few people have allergies to this restorative material;
- Amalgam restoration is both a cheap and more durable solution than white filling (amalgam can last twenty years).
Disadvantages
- The silver colour of the amalgam makes the restoration more visible and therefore less aesthetic;
- Some dental cracks and fractures are associated with the use of amalgam. Constant changes in the internal temperature of the mouth can cause changes in the volume of the material, which contracts in the cold and expands with heat, causing a crack;
- Amalgam has a minimal risk (about 1% of the population) of causing an allergic reaction.
Risks and consequences of not treating
- Progression of dental caries, which can lead to more invasive and costly treatments;
- Loss of tooth.
Processing steps and times
- A local anaesthetic is administered;
- The cavity is removed with a precision instrument called a “dental cutter”;
- The tooth is thoroughly cleaned to eliminate bacteria;
- The amalgam is inserted into the tooth cavity;
- The dentist adjusts the filling and polishes it.
Cost
The cost of restoration varies according to the number of surfaces to be treated.
Cost difference between amalgam and composite resin
If you have to choose between an amalgam or composite resin restoration, it is preferable to find out in advance the cost associated with each of these options and the coverage provided by your insurance.
Currently, RAMQ does not cover composite resin restorations on all teeth. A person who chooses the composite resin for an ineligible tooth will have to pay the full cost of the restoration.
In addition, many insurers only cover a certain percentage of amalgam restorations, and only on certain teeth.
Maintenance
To ensure the longevity of amalgam restorations and to avoid any possibility of infection, it is important to maintain good oral hygiene habits, including regular brushing (2 to 3 times a day), flossing and routine visits to your dentist.
Restrictions
Safety of amalgam restorations
Some people are concerned about the potential health effects of amalgam. Dental amalgams contain several metals including mercury and silver in the form of alloy powder. However, they do not contain lead (as the old term “filling” suggested).
Mercury toxicity
The presence of mercury in amalgam restorations has been raised and questioned many times because of the toxicity of this material. However, according to the Ordre des dentistes du Québec, the amount of mercury in amalgam would not be sufficient to cause any health problems:
“Dental amalgams release mercury vapours, especially during chewing. However, according to the scientific literature, the amount of metallic mercury released is well below the toxicity threshold.
It should also be noted that each individual absorbs another form of mercury from the environment every day. This organic mercury is found in air, water and food such as fish.
According to Health Canada, there is no justification for a complete ban on the use of amalgam or for recommending the replacement of amalgam fillings in good condition in patients. In addition, there is no evidence that dental amalgam is a cause of disease in the general population.”
No studies have shown that amalgam can cause kidney problems or neurodegenerative diseases. The use of amalgam is limited in some countries, including Germany, Denmark, Norway and Sweden. In Quebec, some dentists voluntarily decide not to offer amalgam as a restorative material.
Alternative solutions
- Composite filling;
- Ceramic restoration.