Amalgam fillings, everything you need to know.

Many people know us as a mercury free dental practice, we get asked many times about amalgam fillings and their use within dentistry, we thought the best way to go through many of these things is to create a blog post.

What is an amalgam filling?

A filling is simply your dentist replacing decayed tooth structure with a new material. In days gone by the best material to use to replace this decayed structure was amalgam.

Amalgam consists of silver, tin, copper and approximately 50% by weight of mercury.

Why are dentists still using mercury in fillings?

As a simple to use, manageable, malleable and long-lasting filling material amalgam fits all of the criteria. However, in our opinion, with more health conscious individuals it does not fit the criteria of being the healthiest option for a patient, the dentist or the environment.

How safe is a dental amalgam?

A dental filling releases low levels of mercury, particularly during removal. The information on this website is available to help you understand the potential toxicity or safety of dental amalgam fillings.

The UK Department of Health advises all dentists not to remove or replace amalgam fillings in pregnant women.

Here you can find several documents that can be accessed directly by clicking on the buttons and research articles that you can find online.

How difficult is it to have mercury dental fillings removed?

The actual technique of getting amalgam fillings removed is quite simple, however the safe and holistic way to remove them is to use extensive suction, filters and special burs.

Can an amalgam filling be replaced?

Yes, however it is best removed under very tight control procedures, including, but not limited to:

  1. High-quality ventilation during the removal procedure.
  2. Filters in place to cover your nose and eyes to protect you from daybreak and mercury vapours.
  3. Rubber dam* in place around the tooth to ensure we catch any daybreak and stop it going into your mouth.
  4. High-volume suction to ensure that the mercury vapour is kept to a minimum.
  5. Safe storage of anything which goes into the dental suction chamber.
  6. Continuous water irrigation to keep your feeling cool as it has been shown that more vapour is released with heat.
  7. Specially designed burs which efficiently remove the amalgam was keeping the heat low.

*This is controversial for some people as they believe that the amalgam vapour built up behind the rubber dam, however studies have also shown that treatment with a rubber dam reduces the overall exposure to amalgam during the whole procedure

Why is mercury in dental amalgams?

Mercury was historically used in dental amalgams as it was very pliable at low temperatures meaning that the metal did not need to be heated in order to be placed into the dental cavity, you can imagine how painful it might be having molten metal poured in!

Should I get my silver fillings removed?

The general advice is that if your silver amalgam fillings are working well, not breaking down and the tooth structure around them is sound then leave them as they are. If, however the fillings are beginning to break down then they could either be removed and replaced or, if the breakdown is severe, a dental crown placed over the top.

Why don’t dentists make a silver filling that has no mercury?

Indeed there are many materials which have no mercury including:

  1. Dental composite.
  2. Gold.
  3. Ceramic.

Composite tends to be the cheapest option, is most aesthetic and is amongst one of the easiest materials for the dentist to use. In dental terms it is a relatively modern material which is why amalgam was used historically.

Gold fillings and ceramic inlays have also been used in latter years, gold is falling out of favour due to its cost but ceramic inlays are still used frequently.

Are Composite Resin fillings better than Amalgam fillings?

As with many questions, it depends on who you ask. In our opinion composite resin fillings are indeed better than amalgam fillings for the following reasons:

  • They look better and blend in with the natural teeth.
  • They are simple and easy to repair if they break. Composite can be treated so that it bonds to itself, this means a dentist can easily add more if some chips off.
  • They bond to the tooth structure, this means that your dentist may not need to remove additional tooth structure (After removing the tooth decay) in order to create an undercut that the amalgam would sit in. Composite resin fillings are therefore less destructive on the whole.
  • In very small quantities composite resins can also release fluoride which have a positive effect on the re-mineralisation of your enamel as it is attacked throughout the day.

There has however been research which shows that amalgam has a slightly lower wear rate compared to composite, this could mean that in time composite fillings may need to be replaced more frequently as they wear. In our opinion this slight disadvantage is far outweighed by all of the other advantages of composite resin.

Do holistic dentists help people get healthier? If so, how?

All dentistry can be considered holistic. Links have been found between dental disease and heart disease, diabetes and even erectile dysfunction. The same bacteria has been found in heart disease as is present in those people with gingivitis. The same is true for many other conditions. Looking after your mouth is a very good holistic way to begin looking after your whole body.

Dr Lage has a special interest in Implant Dentistry, Mercury free Dentistry, Root Canal Treatments (Endodontics), and Cosmetic Dentistry (crowns, bridges, veneers, teeth whitening).

He is very calm and very good with children and nervous patients.

Jose speaks English, Portuguese and Spanish and is trying to improve his Italian and French.

What is the best type of dental filling?

What is the best type of dental filling?

As with many things in dentistry and in life the real answer to this question is, it depends. The best type of dental filling depends upon:

  1. The clinical situation.
  2. Your views about the different materials.
  3. Your budget.

In some instances your dentist will prefer to design a dental filling to protect any remaining tooth structure. If this is the case they may turn of filling into what is known as an overlay. An overlay covers any remaining tooth cusps and can protect them from the bite.

Very often this type of dental filling/overlay is made out of porcelain.

Because porcelain is made by a dental technician they can be more expensive than other types of dental filling.

Gold fillings can also be made, once again these are made by a dental technician so have increased cost which added to the cost of the gold can make them quite an expensive alternative.

Composite resin can also be used. These type of composite fillings Are what are known as white fillings. Tooth colored composite fillings are also often used if you want old amalgam fillings replaced. 

Amalgam fillings are not used as much as they used to be. This type of filling material is often associated with mercury poisoning and general health problems. For this reason amalgam fillings are often replaced. There is much written about the science behind amalgam filling replacement, However even the American Dental Association still recommend the use of amalgam.

Glass ionomer can also be used as a white filling, this type of filling material will release fluoride slowly.

Common questions asked about dental fillings.

What is the difference between root canal and teeth filling?

Very simply a dental filling is only in the enamel and dentine of your tooth. The dentist will remove any decayed area and replace it with the dental filling. Root canal is when the nerve of the tooth is removed, this is a much more involved procedure and is often done by a specialist known as and endodontic.

Is it possible to develop a cavity under a filling?

Yes. Good oral health is key to preventing this although fillings, inlays or onlays can leak over the years allowing bacteria and therefore decay to take hold. Unfortunately there is often nothing that can be done about this and the filling simply needs to be replaced. You may find you have the early warning signs of this if you have sudden onset of tooth sensitivity in an area where you have a dental filling.

Can you eat with a temporary filling?

Yes. We do however recommend sticking to food which is not too sticky or chewy. If the temporary filling is towards the front of your mouth then you may also want to avoid food which can sustain for example curry, red wine or lots of tea. The composite material does have a tendency to stain.

How long does it take a dental filling to harden?

Most tooth colored fillings are cured using a high-intensity light in the dental practice, this ensures they have a primary hardening immediately. They do however continue to harden for a little while after although the bulk of this is done within 10 min.

What do fillings on front teeth look like?

A good filling on a front teeth will not look like a filling at all! A good dental filling will blend in so that you don’t even know it exists. This of course will only happen with a tooth coloured filling.

Is a dental filling a very painful process?

No. You will always have a local anaesthetic to numb the area. Also it is recommended that you ask your dentist for a topical anaesthetic first. A topical anaesthetic gel, applied on the end of a little cotton will bud will numb your gum, will numb the area prior to having a dental injection. This means that you can have the injection with no sensation or feeling at all. This should ensure that the whole dental filling procedure is relatively pain-free.

You may experience some mild discomfort as the truth numbness wears off, particularly around where the dental injection was given. This however should be mild discomfort at worst and will clear up after a couple of days

Can a permanent tooth filling stay for a lifetime?

Yes it is possible for tooth filling to last a lifetime however it is not usual. composite fillings tend to last 7 to 10 years whilst metal fillings tend to last 8 to 10 years although they can last up to 20 years. The most common reason that are filling needs to be replaced is due to decay which has managed to creep in around the edge of the filling where it meets the tooth. This can happen with any type of filling regardless of the material.

Are Composite Resin fillings better than Amalgam fillings?

Composite fillings don’t last quite as long as amalgam fillings generally however they are more aesthetic, more biocompatible and for this reason generally more accepted by patients.

Mercury Fillings

With a mercury filling in place

Mercury Filling After

After the mercury filling has been removed and replaced with a composite filling

Do amalgam fillings leak mercury

Amalgam fillings do not generally leak mercury once they are fitted. The critical times for mercury to escape from a filling is whilst the filling is being placed or especially during removal. This is why dental practice which specialises in amalgam filling removal will always use specialist equipment to ensure that any free mercury vapour is extracted away with a dedicated protocol for Mercury replacement.

Dr Lage has a special interest in Implant Dentistry, Mercury free Dentistry, Root Canal Treatments (Endodontics), and Cosmetic Dentistry (crowns, bridges, veneers, teeth whitening).

He is very calm and very good with children and nervous patients.

Jose speaks English, Portuguese and Spanish and is trying to improve his Italian and French.