Amalgam Fillings vs Composite (Tooth Colored) Fillings
 By Mina Levi, DDS, 06/05/2014

Many people have similar questions in mind when they find out that they will be in need of a dental filling. These questions include ones such as “what is the difference between amalgam fillings and composite fillings?” and “which type of filling is right for me?” In this article, we will discuss both amalgam(metal) and composite (tooth colored) fillings, the differences between them and pros and cons of both.

Dentist San Francisco Composite Filling vs Amalgam Filling

Amalgam fillings
Amalgam is a mixture of metals, which consists of liquid mercury and an alloy of silver, tin and copper. Amalgam is about 50% mercury.

   1. Strength. Amalgam fillings are strong, and the amalgam itself is not likely to break easily.
   2. Expense. Amalgam fillings are the least expensive dental restoration.

   1. Mercury poisoning. Amalgam fillings contain mercury, which releases low levels of mercury vapor that can be inhaled. High levels of mercury exposure are associated with kidney and brain problems.

   2. Metal allergies. Although rare, people may have allergies to mercury or the silver, tin or copper found in amalgam fillings and have an adverse reaction to the filling being placed in the mouth.

   3. Poor aesthetics. Amalgam fillings have a silver color and contrast with the white-translucency of the natural tooth structure.

   4. Destruction of healthy tooth structure. Healthy parts of the dental enamel and tooth structure usually need to be removed to make a space large enough to hold the amalgam.

   5. Fractures. All materials contract and expand in the presence of cold and hot liquids; however, amalgam expands and contracts at a different rate than the tooth structure. This causes the tooth to crack and fracture. These fractures, when left untreated, can collect plaque and bacteria and ultimately start decaying the teeth.  

Composite fillings
Composite is a plastic material called synthetic resin. Composite fillings contain no metal alloys.  

   1. Aesthetics. The shade of the composite material used in the filling can be almost identically matched to the original tooth color, no matter what the shade, which allows for blending and a more natural look of the filling.

   2. Keeping healthy tooth structure. Less tooth structure needs to be removed in order to place a composite filling in comparison to the amount of healthy tooth structure that is destroyed when placing amalgam fillings.

   3. Bonding ability. The composite material chemically bonds to the tooth structure, which increases its strength and prevents decay from forming in crevices between tooth structures and filling material, which can happen with amalgam fillings.

   4. Metal-free. Composite fillings are completely metal free and are made of a plastic material, so those who suffer from metal allergies will be completely safe with the resin composite filling.

   5. Versatility. Composite filling material can be used to fill cavities and also to repair chipped or damaged teeth for cosmetic purposes.

   1. Durability. Composite material is not as strong as amalgam, and can chip under pressure of clenching and grinding of the teeth more easily than amalgam will.

   2. More costly. Composite fillings are usually more costly than amalgam fillings, and many insurance companies will only cover up to the amalgam filling fees, leaving the patient with a higher out-of-pocket cost.

If you have any questions regarding amalgam or composite fillings, or think that you may need a filling, give Dentist San Francisco Mina Levi, DDS on the web at or give us a call at (415) 513-5066.