To treat a cavity your dentist will remove the decayed portion of the tooth and then "fill" the area on the tooth where the decayed material once lived.

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 Steps Are Involved in Filling a Tooth?

First, the dentist will numb the area around the tooth to be worked on with a local anesthetic. Next, a drill, will be used to remove the decayed area. The choice of instrument depends on the individual dentist's comfort level, training, and investment in the particular piece of equipment as well as location and extent of the decay.

Next, your dentist will probe or test the area during the decay removal process to determine if all the decay has been removed. Once the decay has been removed, your dentist will prepare the space for the filling by cleaning the cavity of bacteria and debris. If the decay is near the root, your dentist may first put in a liner made of glass ionomer, composite resin, or other material to protect the nerve. Generally, after the filling is in, your dentist will finish and polish it.

Several additional steps are required for tooth-colored fillings and are as follows. After your dentist has removed the decay and cleaned the area, the tooth-colored material is applied in layers. Next, a special light that "cures" or hardens each layer is applied. When the multilayering process is completed, your dentist will shape the composite material to the desired result, trim off any excess material and polish the final restoration.

What Types of Filling Materials Are Available?

Today, several dental filling materials are available. Teeth can be filled with porcelain; silver amalgam (which consists of mercury mixed with silver, tin, zinc, and copper); or tooth-colored, plastic and glass materials called composite resin fillings. The location and extent of the decay, your dentist's recommendation assist in determining the type of filling that will best address your needs.

Silver-fillings (Amalgams)

Advantages:

Durability – lasts at least 10 to 15 years and usually outlasts composite fillings

Strength – can withstand chewing forces

Expense – is less expensive than composite fillings

Disadvantages:

Poor aesthetics – fillings don't match the color of your natural teeth

Destruction of more tooth structure – healthy parts of the tooth must often be removed to make a space large enough to hold the amalgam filling

Discoloration – amalgam fillings can create a grayish hue to the surrounding tooth structure

Cracks and fractures – although all teeth expand and contract in the presence of hot and cold liquids, which ultimately can cause the tooth to crack or fracture, amalgam material – in comparison with other filling materials–may experience a wider degree of expansion and contraction and lead to a higher incidence of cracks and fractures

Allergic reactions – a small percentage of people, approximately 1%, are allergic to the mercury present in amalgam restorations Tooth-colored composite fillings

Advantages:

Aesthetics – the shade/color of the composites can be closely matched to the color of existing teeth; is particularly well suited for use in front teeth or visible parts of teeth

Bonding to tooth structure – composite fillings actually chemically bond to tooth structure, providing further support to the tooth

Versatility in uses – in addition to use as a filling material for decay, composite fillings can also be used to repair chipped, broken or worn teeth

Tooth-sparing preparation –most of the time less tooth structure needs to be removed compared with amalgams when removing decay and preparing for the filling

Disadvantages:

Lack of durability – composite fillings wear out sooner than amalgams (lasting at least 7-10 years compared with at least 10 to 15 for amalgams); in addition, they may not last as long as amalgams under the pressure of chewing and particularly if used as the filling material for large cavities

Increased chair time – because of the process to apply the composite material, these fillings can take up to 20 minutes longer than amalgams to place

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

 

In addition to tooth-colored, composite resin fillings, two other tooth-colored fillings exist–ceramics and glass ionomer.

Other

Ceramics, which are made most often of porcelain, are more resistant to staining than composite resin material but are also more abrasive. Ceramics are rather costly. They require special equipment and may require dental lab support. You may need several appointments. This material generally lasts long.

Glass ionomer 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 (drilling is still required). Glass ionomers release fluoride, which can help protect the tooth from further decay. However, this material is weaker than composite resin and is more susceptible to wear and prone to fracture. Glass ionomer generally lasts 5 years or less .

 

What Are Indirect Fillings?

Indirect fillings are similar to composite or tooth-colored fillings except that they are made in a dental laboratory and require two visits before being placed. Indirect fillings are considered when not enough tooth structure remains to support a filling but the tooth is not so severely damaged that it needs a crown.

During the first visit, decay or an old filling is removed. An impression is taken to record the shape of the tooth being repaired and the teeth around it. The impression is sent to a dental laboratory that will make the indirect filling. A temporary filling (described below) is placed to protect the tooth while your restoration is being made. During the second visit, the temporary filling is removed, and the dentist will check the fit of the indirect restoration. Provided the fit is acceptable, it will be permanently cemented into place.

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.

Inlays and onlays are more durable and last much longer than traditional fillings .

 

Are Amalgam-Type Fillings Safe?

Over the past several years, concerns have been raised about silver-colored fillings, otherwise called amalgams. Because amalgams contain the toxic substance mercury, some people think that amalgams are responsible for causing a number of diseases, including autism, Alzheimer's disease, and multiple sclerosis.

The American Dental Association (ADA), the FDA, and numerous public health agencies say there's no proof that dental fillings cause harm to consumers. The causes of autism, Alzheimer's disease, and multiple sclerosis remain unknown. Additionally, there is no solid, scientific evidence to back up the claim that if a person has amalgam fillings removed, he or she will be cured of these or any other diseases.

Although amalgams do contain mercury, when they are mixed with other metals, such as silver, copper, tin, and zinc, they form a stable alloy that dentists have used for more than 100 years to fill and preserve hundreds of millions of decayed teeth.

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. During this time, avoid those things that are causing the sensitivity. Pain relievers are generally not required.

Contact your dentist if the sensitivity does not subside within 2 to 4 weeks or if your tooth is extremely sensitive. He or she may recommend you use a desensitizing toothpaste, may apply a desensitizing agent to the tooth, or possibly suggest a root canal procedure.

Pain around the fillings can also occur. If you experience pain when you bite, the filling is interfering with your bite. You will need to return to your dentist and have the filling reshaped.

If the decay was very deep to the pulp of the tooth, you may experience a "toothache-type" pain. This "toothache" response may indicate this tissue is no longer healthy. If this is the case, "root canal" treatment will be required.

Sometimes people experience what is known as referred pain -- pain or sensitivity in other teeth besides the one that received the filling. With this particular pain, there is likely nothing wrong with your teeth. The filled tooth is simply passing along "pain signals" it's receiving to other teeth. This pain should decrease on its own over 1 to 2 weeks.

What To Expect After Treatment

After your dentist has filled the cavity, your lips and gums may remain numb for a few hours until the numbing medicine wears off. To avoid injuring your mouth, be careful not to chew on your numb lip or cheek.

Why It Is Done

You need a filling when tooth decay has caused a hole (cavity) to form on a tooth surface. If you don't get a filling, the cavity will get worse and lead to more severe problems, such as bone loss.

How Well It Works

A filling repairs the tooth and stops tooth decay. Over a long period of time, you may need to replace a worn-out filling.
Your filled tooth may be sensitive to heat and cold for days to weeks after you get the filling. Talk to your dentist about toothpastes that may help you with this discomfort. Tell your dentist if your teeth are too sensitive after you get a filling, because you can usually treat this problem.

How Should I Care for My Teeth With Fillings?

To maintain your fillings, you should follow good oral hygiene practices – visiting your dentist regularly for cleanings, brushing with a fluoride-containing toothpaste, and flossing at least once daily. If your dentist suspects that a filling might be cracked or is "leaking", he or she will replace it. If your tooth is extremely sensitive, if you feel a sharp edge, if you notice a crack in the filling, or if a piece of the filling is missing, call your dentist for an appointment.

Risks

There is almost no risk involved in having a cavity filled.
Some dental work can cause bacteria in the mouth to enter the bloodstream. These bacteria can cause infections in other parts of the body. People who have a difficult time fighting infections may need to take antibiotics before and after dental surgery. Such people include those who have artificial heart valves or were born with heart defects.

Timely treatment

It is important to address toothdecay before it gets worse. Severe the decay can be very painfull. It may cost you the tooth (extraction) or you may need an expensive crown or a root canal treatment.