Despite still being the standard approved treatment, metal fillings are becoming less common. New fillings are usually carried out with composite materials, with many patients from clinics in Harley Street to a dentist in Tunbridge Wells opting to have otherwise sound metal fillings removed. So what’s changed and why are so many patients interested in composite alternatives?
Metal amalgam fillings have been used in dental surgeries for decades and were originally a replacement for soft gold fillings. The recipe has been altered, using different types of metals but always with the same shiny silver finish, giving a tough surface suitable for the daily operation of biting surfaces, but impervious to decay. What was considered less important were the aesthetic considerations, with the practicalities of silver or metal fillings taking centre stage and their appearance compared to the older gold fillings and crowns.
How white fillings work
Dental composites use layers of UV cured polymers. By applying each of these as a liquid resin before setting them hard under a UV LED lamp, practitioners have a great degree of control of how quickly and exactly where the resin sets.
The preparation stage is the same as that of the standard filling where decayed material is removed and the remaining tooth can then be treated.
The tough finish of a resin composite filling can be sculpted using a dental drill and will take a fine polish. If the shade of resin has been well chosen to match the patient’s natural enamel, it can be blended seamlessly into the rest of the tooth.
How long will they last?
No fillings last forever and standard metal amalgam ones are replaced every 2 to 4 years. The longevity of any fillings is heavily dependent on the quality of the work when they were installed. By far, the most likely cause of loss is remaining decay that was not adequately cleared out of the tooth before the filling is applied. This decay will eventually loosen a filling, allowing it to come away from the tooth. Another major factor of filling working is thermal expansion; when material is heated (as and when you drink tea for instance) it causes the filling to expand and contract. This is more common with metal than ceramics and this expansion and contraction can result in metal fillings working loose over time, something that we do not see as often with composite materials.
The span of 5 to 7 years is considered a good ballpark average for composite fillings. It is likely that this will increase with the development of higher quality wrapping and with improvement in the techniques revolving around composite use for providing fillings, crowns and in-situ veneering.
Do I have to replace my metal fillings with composite?
There are no medical grounds to replace metal amalgam fillings; they are considered entirely safe, which has been further explored in long-term studies by the General Medical Council and General Dental Council who have both considered the removal of composite fillings to be strictly aesthetic. If you’re happy with your amalgam fillings as they are, there’s no need for you to change them.