They have been around for 100 years now. These traditional fillings are known as “black”, “silver” or “mercury” fillings amongst most patients. The proper name is “amalgam” fillings because the material used is called amalgam. It initially comes as 2 separate components which are mixed together. One of these components is an alloy of silver copper. The other component is mercury. Mercury is obviously toxic but only in that free state. Once it is combined with the alloy, it is actually inert. No mercury goes anywhere near the patient because the mixing is done in a small plastic capsule inside a special mixing machine. Once the dental nurse has the amalgam ready, it is then placed into the cavity and the dentist has only about 5 minutes to shape and make it smooth while it is still soft. Although the filling has 70% hardened once you leave the dental chair, it is not advised to eat straight away on that side for a few hours. The final hardness takes over 24 hours to be reached.
You will read all over the internet and from people that amalgam fillings are dangerous, toxic, cause cancer and cause every disease known. Have you ever heard the term that a little knowledge is a dangerous thing. Well this phrase is so true in this case!There is actually not a single study which shows conclusively that amalgam is a health risk. It is all based on circumstantial evidence. This does not however stop the many companies, organisations, alternative health gurus and even dentists themselves to “cash” in on alternatives and all manner of cures for so called symptoms of mercury poisoning. If you think that white fillings are safe, then don’t forget that white fillings have been shown to contain harmful and cancer causing ingredients. If you are ever contemplating to have your old fillings changed, my advice is always, “leave well alone” if you have amalgam fillings. Even when they need replacing, amalgam is still the best material if you want your fillings to last a long time. I use a meticulous technique to reduce any theoretical harmful exposure to myself, my staff and the patient so there is really no need to worry about things. A major reason as to why amalgam fillings outlast any other material for fillings is that amalgam forms the best seal around the tooth. This seal is vital to stop decay and bacteria getting in underneath the filling and into the nerve of the tooth. Obviously as with all things, eventually the filling will wear out or start leaking which is then the ideal time to have the filling changed.
I treat patients where these fillings were placed by myself over 25 years ago in dental school when I was training and these same fillings are still going strong. In fact some elderly patients have now even passed away but their amalgam fillings were still intact.
White fillings are a cosmetic option and for patients who are worried about the health risk even though the theoretical health risks of amalgam is not conclusive. All white fillings have disadvantages in terms of cost, how long they will last and complications such as tooth sensitivity afterwards. You can read more about white fillings by clicking on the link.
On the NHS amalgam fillings come under a Band 2 treatment. This means that the cost is fixed and determined by the government. Amalgam fillings can also be done privately and the main advantage is that there are no time constraints so the filling can be really well polished and sealed which means it will last longer.
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