When you get a cavity in one of your teeth, you will need to get a filling. This is also called a “restoration” because it involves repairing and renewing a tooth. There are several main options for dental fillings – talk with your dentist to determine which option is best for you.
Fillings fall into two main categories: direct and indirect restorations. The type of filling you receive is affected in part by the type of restoration you need.
In a direct restoration, the work is fairly straightforward and uncomplicated –the dentist is able to remove any tooth decay, create the filling and complete the work of repairing the tooth all within the same office visit.
With an indirect restoration, the dental work is usually a bit more complicated and requires two or more visits to your dentist – for example, there might be bridgework involved that affects multiple teeth, or crowns or veneers to repair damaged teeth, or other complications. Your dentist will take an impression of your affected teeth and send the work to a dental laboratory to create the permanent restoration. Then, at a follow-up appointment, your dentist will do the final step of cementing the restoration onto your teeth.
Depending on whether you need a direct or indirect restoration, you and your dentist can choose from the following types of filling materials. Each one has its various advantages and disadvantages; your dentist can help you decide on the material that is best for your needs.
Direct restoration fillings:
- Amalgam: This is the most common type of filling and has been used for over 100 years. The amalgam is made from a mixture of mercury, silver and other metals – they are often called “silver fillings” because of their silver color.
- Advantages: Inexpensive, durable, highly resistant to further tooth decay, and can usually be placed in just one office visit. Amalgam also performs well as a biting surface – it holds up to the pressures and wear of chewing and eating over time.
- Disadvantages: Placement of amalgam requires the removal of a small amount of healthy tooth material. Amalgam also tends to be less attractive looking than some of the other options for filling material – after all, natural teeth are not silver. For this reason, amalgam fillings are usually used only on the back teeth.
A note about amalgam and mercury: Some individuals and advocacy groups have questioned the safety of dental amalgam because it contains mercury and releases a small amount of mercury vapor over the course of its life. Dental amalgam has been the subject of numerous research studies over the years, and no valid scientific research has proven that dental amalgam causes harm to patients, except in rare cases of allergy. So if you need to get amalgam fillings, rest assured that they are safe – and if you do have an allergy to the materials, a different filling can be used.
- Composite resin: Composite is made from a combination of acrylic resin and glass-like particles that create a natural-looking tooth material.
- Advantages: Natural looking – the color can be matched to your existing teeth. It tends to allow for the preservation of a greater portion of the original tooth.
- Disadvantages: Composite fillings are usually more expensive than metal fillings. They also tend to wear down faster and can be prone to breaking more often – resulting in the need for additional dental work in the future to repair or replace the fillings. Composite fillings cannot be used for certain situations – as always, talk to your dentist.
- Glass ionomer: Glass ionomers are made from acrylic and glass powder and are used primarily for small fillings.
- Advantages: Natural tooth color. Low incidence of allergic reaction – most people do not have allergies to this material. Glass ionomer fillings can be made to include fluoride to help resist further tooth decay.
- Disadvantages: This is not as durable of a filling material as the other options – it is only used for small fillings and in areas that are not subject to a lot of heavy biting and chewing. This material can become rough as it ages, resulting in plaque buildup. It is also more costly than amalgam fillings – similar in price to composite resin.
- Resin ionomer: This type of filling is made from glass filler, acrylic acids and acrylic resin. It is often used for fillings in baby teeth and on non-chewing surfaces.
- Advantages: Natural tooth color – is even more translucent than glass ionomer fillings. Can contain fluoride. More durable than glass ionomer.
- Disadvantages: Not recommended for biting surfaces in adult teeth; less durable than composite and amalgam.
Indirect restoration fillings:
- Porcelain (ceramic): This type of filling material is commonly used in indirect restorations. The ceramic porcelain can also be fused to metal as part of the tooth restoration – which improves the durability of the filling but also increases the complexity and cost of the dental work.
- Advantages: Natural tooth color. Requires very little healthy tooth material to be removed.
- Disadvantages: Tends to be more brittle than other materials. May not be recommended for molars. Usually requires two or more office visits to place the filling, and tends to be more costly.
- Gold (or other metal) alloy: Gold alloys (containing gold, copper and other metals) are another option for indirect restorations.
- Advantages: Excellent durability, does not break under stress.
- Disadvantages: Gold is usually the highest-cost option for a filling. Not a “natural” tooth color.
As always, talk with your dentist to find the right choice of fillings for your needs.