Dental health and tooth fillings

Silver fillings (amalgams)

Advantages of silver fillings:

1. Durability. Silver fillings last at least 10 to 15 years and usually outlasts composite fillings.
2. Strength. Can withstand chewing forces.
3. Expense. Is less expensive than composite fillings.

Disadvantages of silver fillings:

1. Poor aesthetics. Silver fillings don't match the colour of your natural teeth.
2. Destruction of more tooth structure. Healthy parts of the tooth must often be removed to make a space large enough to hold the amalgam filling.
3. Discolouration. Amalgam fillings can create a greyish hue to the surrounding tooth structure.
4. Cracks and fractures. Although all teeth expand and contract in the presence of hot and cold liquids, which ultimately can cause the tooth to crack or fracture, amalgam material, in comparison with other filling materials, may experience a wider degree of expansion and contraction and lead to a higher incidence of cracks and fractures.
5. Allergic reaction. Approximately 1% of people are allergic to the mercury present in amalgam restorations.

Tooth-coloured composites

Advantages of composites:

1. Aesthetics. The shade/colour of the composite fillings can be closely matched to the colour of existing teeth and is particularly well suited for use in front teeth or visible parts of teeth.
2. Bonding to tooth structure. Composite fillings actually chemically bond to tooth structure, providing further support to the tooth.
3. Versatility in uses. In addition to use as a filling material for decay, composite fillings can also be used to repair chipped, broken or worn teeth.
4. Tooth-sparing preparation. Sometimes less tooth structure needs to be removed compared with amalgams when removing decay and preparing for the filling.

Disadvantages of composites:

1. Lack of durability. Composite fillings wear out sooner than amalgams (lasting at least five years compared with at least 10 to 15 for amalgams). In addition, they may not last as long as amalgams under the pressure of chewing and particularly if used as the filling material for large cavities.
2. Increased “chair time”. Because of the process to apply the composite material, these fillings can take up to 20 minutes longer than amalgams to place.
3. Additional visits. If composites are used for inlays or onlays, more than one surgery visit may be required
4. Chipping. Depending on location, composite materials can chip off the tooth.
5. Expense. Composite fillings can cost up to twice the cost of amalgams.

In addition to tooth-coloured, composite resin fillings, two other tooth-coloured fillings exist: ceramics and glass monomer.

Other filling types

1. Ceramics. These fillings are made most often of porcelain, are more resistant to staining than composite resin material but are also more abrasive. This material generally lasts more than 15 years and can cost as much as gold.
2. Glass monomer is made of acrylic and a specific type of glass material. This material is most commonly used for fillings below the gum line and for fillings in young children (drilling is still required). Glass monomers release fluoride, which can help protect the tooth from further decay. However, this material is weaker than composite resin and is more susceptible to wear and prone to fracture. Glass monomer generally lasts five years or less with costs comparable to composite resin.