Composites and fillings

Composites are resin-based filling materials which consist of a polymer and different types of fillers. Composite resins possess the unique capability of matching the colour of the adjacent teeth. As a result, they provide excellent aesthetics and lifelike appearance to restored teeth.

Placement of composite fillings is a simple procedure which is completed in a single sitting.

• First, your dentist will place a sheet of rubber dam over your mouth, isolating the tooth to keep it dry as the composite filling materials are sensitive to saliva until they are set.
• The dentist will then remove the damaged tooth structure.
• Next, the area will be cleaned with irrigation of water and dried. If the cavity is too deep, your dentist will first place a lining agent to protect the underlying pulp from accidental exposure.
• Afterwards, an acidic gel will be applied over the tooth surface for 30 seconds, where the filling will be placed. The gel is then washed away, and the composite filling is applied in small increments.
• Each increment is then hardened with the help of a special light source.
• Once the final increment has been placed, the filling is shaped and polished to provide maximum aesthetics and to prevent future chances of the development of tooth cavities.

Composite fillings are the most favoured filling materials, both among the patients and the dentists, due to a variety of reasons. Most importantly, composite fillings can exactly match the shade of adjacent teeth. Therefore, when a tooth is restored, it becomes virtually indistinguishable from the natural teeth. Secondly, unlike silver amalgam fillings, composite fillings do not require excessive tooth removal as they can ‘bond’ to tooth structure, compared with silver amalgam fillings, which rely on ‘locks’ being cut into the tooth structure (like a jigsaw puzzle piece).

Previously, white fillings or composites have always been considered less long-lasting than silver amalgam fillings. But there are now new materials available with properties comparable to silver amalgam, and these are proving to be very successful.

The life expectancy of a white filling can depend greatly on where it is in your mouth and how heavily your teeth come together when you bite. Because of this, in certain cases, your dentist may advise you against placing white fillings in back teeth as they are not always successful.

Composite fillings can sometimes cause sensitivity as the filling material ‘shrinks’ slightly during the setting stage. We often leave a ‘lining’ underneath the composite filling, which creates a seal over the nerves of the teeth to prevent sensitivity.

Dental amalgam has been used for more than 150 years in hundreds of millions of patients around the world.
Dental amalgam is a mixture of metals, consisting of liquid (elemental) mercury and a powdered alloy composed of silver, tin, and copper. Approximately 50% of dental amalgam is elemental mercury by weight. The chemical properties of elemental mercury allow it to react with and bind together the silver/copper/tin alloy particles to form an amalgam.

• When placing dental amalgam, the dentist first drills the tooth to remove the decay and then shapes the tooth cavity for placement of the amalgam filling.
• Next, the dental assistant mixes the amalgam ingredients (which are sealed in a capsule) at high speed to form an amalgam putty.
• This softened amalgam putty is placed and shaped in the prepared cavity, where it rapidly hardens into a solid filling.

Dental amalgam fillings are strong and long-lasting, so they are less likely to break than some other types of fillings. Silver amalgam fillings are more economical than composite fillings as the materials are less expensive and the treatment can often be completed in a shorter appointment time. Amalgam fillings are still one of the leading materials for restoring teeth.

Dental amalgam fillings are ‘unsightly’ compared with composite alternatives.

Although amalgam fillings do contain elemental mercury, these fillings are safe for adults and children ages six and above. Clinical studies in adults and children ages six and above have found no link between dental amalgam fillings and health problems.

In 2017, a new EU ruling meant that amalgam fillings cannot be placed in deciduous (baby) teeth of children under 15 years old or pregnant or breastfeeding women, except when strictly deemed necessary by the treating dentist. This EU directive has been put in place to purely reduce the amount of waste for environmental reasons only.

Another alternative option to a silver or composite filling would be to use crowns or inlays, but this can mean removing more of the tooth and can be more expensive. Your dentist will always advise you on the most accurate treatment option for you personally.