Thanks to advances in technology, dentists and patients today have a variety of options when it comes to selecting materials for filling cavities. Options include natural tooth-colored materials, such as resin-based composite fillings, and more traditional dental fillings, such as those made from metallic amalgam.
The appearance of new materials for fillings has been beneficial, especially in terms of aesthetics, but it does not eliminate the relevance of traditional dental materials that are stronger, more durable, and cheaper. These materials are best in situations where restored teeth must withstand extreme forces that result from biting, such as in the back of the mouth.
What is a dental amalgam?
Most people recognize dental fillings as silver fillings. Dental amalgam is a mixture of mercury, silver, tin, and copper. Mercury, which makes up about 50% of the compound, is necessary to bond metals together to provide a strong, hard, and long-lasting filling. After years of research, mercury remains the only element that can bind these metals in a way that can be easily manipulated to fill cavities.
Dentists often prefer dental amalgam because it is easier to manipulate than other alternatives. Many dentists consider amalgam to be stronger than resin-based composite filling and therefore use amalgam for fillings in posterior teeth. Many patients prefer dental amalgam for the same reasons, in addition to its cost-effectiveness and ability to fill cavities quickly. It is estimated that more than 1 billion amalgam fillings are placed per year.
What are resin-based composite fillings?
Resin-based composite fillings are made of ceramic and plastic composites. Since the resins mimic the appearance of natural teeth, these fillings have been used on front teeth for years. However, when they first appeared, the resin composites were not strong enough to be used on posterior teeth, where chewing and high-pressure grinding require greater durability.
In the last 10 years, technology has improved enough to allow the use of resin materials in posterior teeth. Still, many dental plans, including Dentegra, do not cover resin fillings on teeth that are not visible when smiling, and many dentists choose not to use resin for one or more of these reasons:
Since the most durable resin material has been available for only a decade, the resins have not stood the test of time on teeth where chewing and grinding produce great wear; on the contrary, the durability of amalgam fillings is well documented: the average life of amalgam fillings is 8 to 10 years, but many last 20 years or more.
Amalgam is one of the best filling materials when dentists have to place them in areas of the mouth that are difficult to keep dry, such as molars (back teeth) or cavities below the gum line. Resin fillings must be placed in a specific environment; for example, the prepared tooth must be completely dry when the resin material is applied and hardened. Clinical experience has consistently shown that amalgam is still, for many reasons, the most reliable filling material for long-term, low-maintenance function.
Resin costs more than amalgam, which can make the service cost higher than a comparable amalgam filling service.
For these reasons, most dental health insurance companies pay coverage for resin fillings on teeth that are visible when the patient smiles. For example, virtually all Dentegra plans cover resin fillings on teeth where the cosmetic benefit is critical: the six front teeth (incisors and cusps) and on the facial surfaces (the cheek side) of the next two teeth. (bicuspids).
ADA and FDA Recommendations for Fillings
Dental amalgam has a proven 150-year history as one of the safest, most durable, and least expensive materials used to fill cavities. The constant scientific studies that have been carried out in the last 100 years continue to show that amalgam is not harmful.
Much of the concern regarding the safety of amalgam arises from the use of mercury as a bonding agent. But when the mercury combines with other materials in dental amalgam, its chemical nature changes and it becomes harmless. The amount of mercury that is released into the mouth under the pressure of chewing and crushing is extremely small and is not a cause for concern. It is less than the amount patients are exposed to through food, air, and water, and less than is released by patients who choose to have an existing amalgam filling removed.
The American Dental Association (ADA) maintains that dental amalgam remains a safe, affordable, and long-lasting option as a filling for cavities in dental patients. The United States Food and Drug Administration (FDA) does not recommend the removal of amalgam fillings in patients who have them because this could cause further damage to the tooth structure and pose other health risks for the patient.
The patient and dentist should decide what type of filling will be used, taking into account the size and location of the decay, the patient’s history, cosmetic concerns, and cost. Ask your dentist to discuss all the options available for dental fillings and to help you decide which alternative is right for you.
