There are two main filling materials available to dentists, namely composites and amalgam.

Composites

A composite resin is a tooth-colored plastic mixture filled with glass (silicon dioxide).
Composites are not only used to restore decayed areas, but are also used for cosmetic improvements of the smile by changing the color of the teeth or reshaping disfigured teeth.

The main advantages of composites are:

   • They are available in many shades of tooth colours, and can be mixed and matched to
      create the exact colour of the part of tooth being replaced.
   • They are bonded/glued to the tooth and thus the dentist need only remove the decayed
      part of the teeth prior to filling. This means that all healthy tooth structure can be
      preserved. This is not the case for amalgam fillings.
   • They are ultra-violet light-cured by the dentist and therefore set hard immediately.
   • They do not contain mercury (see below)

The disadvantage of composite resin is that, on the front teeth, it does have to be replaced after several years due to colour changes. The colour changes occur from coffee, tea, red wine or smoking.

Amalgam

Amalgam fillings are silver coloured. They are made by combining mercury and a silver alloy (50% mercury, 35% silver, 15% tin, copper and other metals). Amalgam is long lasting and hard wearing and has been used in fillings for at least 150 years.
Mercury makes up about 45-50 percent of the compound. Mercury is used to bind the metals together and to provide a strong, hard durable filling. After years of research, mercury has been found to be the only element that will bind these metals together in such a way that can be easily manipulated into a tooth cavity.

Why should I consider white fillings?

Most people have fillings of one sort or another in their mouths. Nowadays fillings are not only functional, but can be natural looking as well. Many people don’t want silver fillings that show when they laugh or smile because they are more conscious about the way they look.

Why do dentists use dental amalgams?

Dental amalgam has withstood the test of time, which is why it is still in use. It has a 150-year proven track record and is still one of the durable and least expensive materials to a fill a cavity. It is estimated that more than 1 billion amalgam restorations (fillings) are placed annually.

One property of amalgam which is causing particular problems nowadays, is their failure to bond to tooth structure. This over the years, leads to microfractures and cracks in teeth. It is now not uncommon for many patients to suffer with cracked tooth syndrome under amalgam filled teeth. This applies in particular to large amalgam fillings which are over 10 years old.

Is mercury in dental amalgam safe?

The amount of mercury released in the mouth under the pressure of chewing and grinding is extremely small and no cause for alarm. However, links remain between levels of mercury in the brain and body, and the occurrence of Alzheimer’s Disease, gastrointestinal problems, sleep disturbances, concentration problems, memory disturbances, lack of initiative, restlessness, bleeding gums and other mouth disorders.