Whether you need an existing filling replaced or a new cavity filled, get the facts on what your options are. Gone are the days when cast gold and silver amalgams were your only choices. With dental care advancements, other materials are also being used to fill cavities. Here are the advantages and disadvantages of the four most common filling materials.
Types of Fillings
1. Silver Amalgam Fillings: Dental amalgam has been used to fill cavities for more than 150 years. Also known as "silver fillings", it contains a mixture of metals — consisting of liquid mercury and a powdered alloy. Amalgam fillings have proved the test of time due to their durability, strength and affordability. Silver fillings will last at least 10 years and can withstand chewing forces.
Although amalgam has been used for years, there are both structural and cosmetic disadvantages to this type of filling. The process of creating and fitting an amalgam filling often forces the dentist to remove healthy parts of the tooth. Amalgam fillings will also expand and contract with temperatures in your mouth, which over time can result in the filling pulling away from the tooth. Additionally, silver fillings will not match the color of natural teeth and can create discoloration of the tooth surrounding the filling.
2. Cast Gold Fillings: Cast gold fillings are comprised of gold mixed with other metals to form an alloy. Unlike other filling materials that usually last 5 to 10 years, cast gold fillings last at least 15 years, if not longer. They will not corrode and are extremely durable against chewing forces. However, they do come with a price tag. Cast gold fillings are one of the most expensive filling materials and cost more than amalgam, composite resin and glass ionomer.
There are other disadvantages to gold cast fillings beside cost. They require you to visit the dentist at least twice — initially to take a tooth impression and place a temporary filling and next to place the gold filling. Similar to amalgam fillings, gold fillings are not aesthetically appealing and will not match your natural teeth color. They can also cause discomfort; if placed next to an amalgam filling you may experience an electric current in your mouth known at "galvanic shock."
3. Glass Ionomer Fillings: Glass ionomer is a tooth colored material that is often used as cement for inlay fillings, which lie within the cusps of teeth on the chewing surface. It may also be used for fillings in front teeth or in roots, typically for patients who have a lot of decay extending below the gum. In addition to matching the color of the teeth, glass ionomer provides protection through the release of fluoride and easily bonds to teeth to prevent leakage around the filling and further decay.
Unlike other filling materials, glass ionomer is weaker in structure. On average, glass ionomer fillings have a greater chance of fracturing and will last around five years. Additionally, the filling process with glass ionomer takes longer than with other materials because it needs to be applied in thin layers.
4. Composite Resin Fillings: If aesthetics is your primary concern, composite resin fillings are ideal. Dentists can blend multiple shades to create a color that is almost identical to that of natural teeth. Composite resin fillings are made of a plastic and glass mixture and can be used for both small and large fillings.
Not only will they match your natural teeth color, but also they bond directly to the teeth making them stronger. They also require less drilling than amalgam fillings and can be used with some other materials to provide the perfect filling for your cavity. Similar to glass ionomer, composite resin fillings will only last about five years. Additionally, the composite may shrink when placed on the tooth, which can lead to gaps between the tooth and filling, a potential hazard for more cavities.
Now that you know the facts, you will be prepared to discuss the options with your dentist. Of course, your dentist is your most valuable resource when selecting which filling material to proceed with. Based on the location and extent of the decay, he or she will determine what is best for you.
Dental Health and Tooth Fillings. (2015, January 26). Retrieved June 8, 2015, from http://www.webmd.com/oral-health/guide/dental-health-fillings
Fillings. (2014, March 7). Retrieved June 8, 2015, from http://www.medicinenet.com/fillings/page2.htm#what_types_of_filling_materials_are_available