Which dental filling is best for the problem you have? Well, there are basically three kinds to choose from, and the decision is going to be a whole lot easier than you think, as glass ionomer tooth fillings are not available yet, and amalgam dental fillings have been made illegal. But a description of the pros and cons of all three can be very useful in understanding how dental fillings work, what they do and the properties of each of the materials used.
Amalgam tooth fillings are an admixture of silver, mercury, tin, and a whole host of other trace metals to form an alloy that is resistant to wetness and does not corrode, is safe enough, and lasts a lifetime. It is easy to make and most dentists can make them at their dentistry and is super inexpensive. The downside is that the mining and use of mercury have been deemed unethical and is banned in the EU, Japan and many other countries by the Minamata Convention.
The tooth fillings may also leach mercury, which is very bad, as this material causes brain damage, is toxic to humans and is carcinogenic. The other downside is unlike the other two dental fillings on this list, amalgam tooth fillings do not strengthen the teeth, merely fill up the gap that is left by bacterial corrosion. They also look bad, because they make the teeth look darker, and the dental fillings themselves are black and not very aesthetic at all.
These dental fillings strengthen the teeth, are tooth coloured so they blend right in, and so are more hospitable to the tooth they are in. They are also fairly easy to make, but a little bit harder than amalgam. Their main downside is that they decay, meaning you will have to get a new tooth filling every six years or so. This can cause serious problems, as the dental filling will get smaller and smaller over time. These dental fillings also leach trace amounts of BPA, which messes with the hormonal makeup of patients, contributes to obesity and can be carcinogenic.
Burnt, liquefied and ionised glass is most definitely the best kind of tooth filling. It is just as durable as an amalgam filling, but cannot leach anything, and is just as aesthetically pleasing as a composite white dental filling. The downside is that this is still in the clinical phase, and will require quite a bit of artistry and fancy equipment to make, so they may be more expensive than both of their counterparts.