If you have a cavity and it needs a filling, there are different kinds of fillings to do the job.
Your dentist cares about you and your oral health. If you have any questions or concerns about fillings, talk to your dentist. He or she will advise you on the type of filling that works best in your particular case, and inform you about the aesthetic and cost implications for each type.
There are several different types of fillings that can be used to fill a cavity, but the final decision on which type of filling is placed in your mouth is yours alone.
How Fillings Are Done
To fill a cavity, your dentist may first give you “freezing” (or local anesthetic), so you do not feel any pain. Your dentist then takes out all traces of decay, shapes the hole and fills it.
Most fillings are done in two ways:
- Direct Filling – These fillings go right into the cavity, after your dentist has cleaned out the decay. Amalgam (or silver) fillings and plastic (or white) fillings are examples of direct fillings. They harden quickly. Most of the time, you will be able to have a direct filling put in place in one appointment.
- Indirect Filling – Examples of this type of filling are inlays and onlays. They are custom made in a lab to fit your tooth. Your dentist cements the filling in place. Most indirect fillings take two or more appointments to complete.
Dental amalgam is the best-known direct material. Cast gold alloy is the most durable indirect material. However, ceramics are gaining in popularity because of their longevity relative to other tooth-coloured materials.
Remember, your dentist is interested in you and your oral health. If you are concerned about having any particular dental restorative materials placed in your teeth, talk to your dentist and be a partner in decisions about your oral health care.
Health Canada’s Role
One of Health Canada’s jobs is to make sure that dental fillings and dental tools are safe. The Canadian Dental Association (CDA) supports Health Canada’s role in making sure that Canadians receive the best possible care when they visit their dentist.
Dental Amalgam Fillings
Dental amalgam fillings are sometimes called “silver” fillings. They are the most common type of filling used in Canada today. Because these fillings are silver in colour, they are used to fill back teeth. They are a mix of metals such as mercury, silver, copper and tin.
- These fillings are the least expensive type of filling.
- They last a long time.
- They are easy to put in place; because they are a direct filling, one visit to your
- dentist will do the job, in most cases.
- The silver colour may not appeal to people who want a “natural” look.
- Tiny amounts of mercury are released from the filling when you chew. For most people, this bit of mercury is nothing to worry about. Studies have shown that amalgam fillings do not cause illness. They have been used on people for more than 150 years.
- Health Canada advises pregnant women in need of a filling to wait until the baby is born before they go ahead with the procedure. Your dentist can suggest other kinds of fillings, if the work is urgent.
Cast Gold Fillings
Cast gold fillings are based on a model (or cast) of your tooth. Cast gold fillings are a mixture of gold with other metals such as silver and copper. These other metals make gold fillings more durable.
A cast gold filling is made in a dental lab and sent back to your dentist, who cements it in place in your mouth. You will need at least two visits to the dentist to get the job done. During the first visit, your dentist cleans out all the decay and makes a mold of your tooth. The hole is filled with a temporary filling.
Meanwhile, in a dental lab, the mold of your tooth is used to make a model. A filling that is the same size and shape as your tooth is built, based on the model. When you go back to the dentist a couple of weeks later, the gold filling is cemented in place.
- Gold is stronger than amalgam.
- Gold fillings last a long time.
- Gold costs more than other kinds of fillings.
- Gold fillings and crowns are indirect fillings, so they require at least two appointments.
- The gold colour may not appeal to people who want a “natural” look.
Composite fillings and fillings made out of glass ionomer materials are the same colour as your natural teeth.
Composite fillings are also called plastic or white fillings. Getting this kind of filling depends on where the tooth is in your mouth. We bite down hard on our back teeth (molars), so a plastic filling may not be a good choice. Talk to your dentist about other options.
To place this filling, your dentist cleans all decay from the tooth and puts a glue (or bonding material) on the inside of the hole. Composite resin is put into the hole in thin layers. Each layer gets hard with the help of a special light that your dentist holds over the tooth. When the last layer of the filling is hard, your dentist shapes the filling so it looks and feels natural.
- These fillings will be the same colour as your natural teeth.
- They cost less than gold fillings.
- They are direct fillings, so they can be done in one appointment, in most cases.
- This kind of filling can break more easily than amalgam or gold fillings, and may not last as long.
- Composite fillings cost more than amalgam fillings.
- Recurrent decay is more of a problem than with amalgam or gold fillings.
Glass Ionomer Materials
Glass ionomer materials are only used in teeth where you do not bite down hard. There have not been many studies about how long this kind of filling lasts. Newer forms of the filling may be stronger and last longer. Research is underway to evaluate the effectiveness of these materials.
- These fillings are the same colour as your natural teeth.
- They contain fluoride, which helps stop recurrent decay in the tooth.
- They do not have to be put in layer by layer; thus, they are simpler to put in than composite resins.
- They are direct fillings and can be done in one appointment, in most cases.
- They cost less than gold fillings.
- They are not as strong and will not last as long as other fillings.
- They cost more than amalgam fillings.
Porcelain materials are the most common type of dental ceramic used by dentists. They are hard and brittle. Porcelain and metal can be combined to make a strong, tooth-coloured crown.
Dental porcelain is made in a dental lab. Unless you have a bad tooth-grinding habit or some other problem, a combination of porcelain and metal can be used anywhere in the mouth.
- Dental porcelain is the same colour as natural teeth.
- These fillings last a long time.
- For teeth that bite down hard – like molars – ceramics are not a good choice. Fillings can break.
- They are indirect fillings, so at least two appointments will be needed.
- They cost more than most other types of fillings.