Fillings are also used to repair cracked or broken teeth and teeth that have been worn down from misuse (such as from nail-biting or tooth grinding).
What Types of Filling Materials Are Available?
Today, several dental filling materials are available. Teeth can be filled with gold; porcelain; silver amalgam (which consists of mercury mixed with silver, tin, zinc, and copper); or tooth-colored, plastic, and materials called composite resin fillings. There is also a material that contains glass particles and is known as glass ionomer.
Cast Gold Fillings
Advantages of cast gold fillings:
- Durability - lasts at least 10 to 15 years and usually longer; doesn't corrode.
- Strength - can withstand chewing forces
- Aesthetics - some patients find gold more pleasing to the eye than silver amalgam fillings.
Disadvantages of cast gold fillings:
- Expense -- gold cast fillings cost more than other materials; up to 10 times higher than cost of silver amalgam fillings.
- Additional office visits -- requires at least two office visits to place.
- Galvanic shock -- a gold filling placed immediately next to a silver amalgam filling may cause a sharp pain (galvanic shock) to occur. The interaction between the metals and saliva causes an electric current to occur. It's a rare occurrence, however.
- Aesthetics -- most patients dislike metal "colored" fillings and prefer fillings that match the rest of the tooth.
Silver Fillings (Amalgams)
Advantages of silver fillings:
- Durability -- silver fillings last at least 10 to 15 years and usually outlasts composite (tooth-colored) fillings.
- Strength -- can withstand chewing forces.
- Expense -- is less expensive than composite fillings.
Disadvantages of silver fillings:
- Poor aesthetics -- silver fillings don't match the color of natural teeth.
- Destruction of more tooth structure.
- Cracks and fractures.
- Allergic reactions.
Advantages of composites:
- Bonding to tooth structure.
- Tooth-sparing preparation.
Disadvantages of composites:
- Lack of durability.
- Increased chair time.
- Additional visits -- if composites are used for inlays or onlays, more than one office visit may be required.
- Chipping -- depending on location, composite materials can chip off the tooth.
- Expense -- composite fillings can cost up to twice the cost of amalgam fillings.
In addition to tooth-colored, composite resin fillings, two other tooth-colored fillings exist -- ceramics and glass ionomer.
Other Filling Types
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.
Glass 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.
What Are Indirect Fillings?
Indirect fillings are similar to composite or tooth-colored fillings except they are made in a dental laboratory and require two visits before being placed.
There are two types of indirect fillings -- Inlays and Onlays.
- Inlays are similar to fillings but the entire work lies within the cusps (bumps) on the chewing surface of the tooth.
- Onlays are more extensive than inlays, covering one or more cusps. Onlays are sometimes called partial crowns.
What's a Temporary Filling and Why Would I Need One?
Temporary fillings are used under the following circumstances:
- For fillings that require more than one appointment -- for example, before placement of gold fillings and for certain filling procedures (called indirect fillings) that use composite materials.
- Following a root canal.
- If emergency dental treatment is needed (such as to address a toothache).
Are Amalgam-Type Fillings Safe?
Over the past several years, concerns have been raised about silver-colored fillings, otherwise called amalgam fillings. Because these fillings contain the toxic substance mercury, some people think they are responsible for causing a number of diseases, including autism, Alzheimer's disease, and multiple sclerosis.
How Should I Care for My Teeth With Fillings?
To maintain fillings, you should follow good oral hygiene -- visiting your dentist regularly for cleanings, brushing with fluoride toothpaste, flossing and using an antibacterial mouthwash at least once daily.
Problems with Dental Fillings
Tooth Pain and Sensitivity
Tooth sensitivity following placement of a filling is fairly common. A tooth may be sensitive to pressure, air, sweet foods, or temperature. Usually, the sensitivity resolves on its own within a few weeks.
Contact your dentist if the sensitivity does not subside within two to four weeks.
Allergic reactions to silver fillings are rare
Constant pressure from chewing, grinding, or clenching can cause dental fillings to wear away, chip, or crack.