What are the advantages and disadvantages of dental filling materials? What are indirect fillings? Are silver amalgams safe? Can you be allergic to amalgam fillings? These and other popular questions are answered.
Dental fillings are single or combinations of metals, plastics, glass or other materials used to repair or restore teeth. One of the most popular uses of fillings is to “fill” an area of tooth that your dentist has removed due to decay – “a cavity.” 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).
Dental filling materials include:
The location and extent of the decay, cost of filling material, your insurance coverage and your dentist’s recommendation help determine the type of filling that will best address your needs.
Yes. Advantages and disadvantages of the various dental filling materials are as follows:
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 you don’t have enough tooth structure remains to support a filling, but your 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 makes 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 checks the fit of the indirect restoration. If the fit is acceptable, it will be permanently cemented into place.
There are two types of indirect fillings – inlays and onlays.
Inlays and onlays are more durable and last much longer than traditional fillings – up to 30 years. They can be made of tooth-colored composite resin, porcelain or gold. Inlays and onlays weaken the tooth structure, but do so to a much lower extent than traditional fillings.
Another type of inlay and onlay – direct inlays and onlays – follow the same processes and procedures as the indirect, the difference is that direct inlays and onlays are made in the dental office and can be placed in one visit. The type of inlay or onlay used depends on how much sound tooth structure remains and cosmetic concerns.
You might need a temporary fillings:
Temporary fillings are just that; they are not meant to last. They usually fall out, fracture, or wear out within one month. Be sure to keep your appointment to have your temporary filling replaced with a permanent one. If you don’t, your tooth could become infected or you could have other complications.
First, your dentist will numb the area around the tooth to be worked on with a local anesthetic. Next, a drill, air abrasion instrument or laser will be used to remove the decayed area. The choice of instrument depends on your 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.
The American Dental Association (ADA), the FDA and numerous public health agencies say that silver (mercury based) amalgam fillings are safe. However, the FDA recently issued updated recommendations about the use of amalgam fillings in certain individuals. They state that the following individuals may be at greater risk for potential harmful health effects of mercury vapors and should avoid getting these fillings whenever possible.
The FDA does not recommend removing dental amalgam in people at higher risk if the amalgam is in good condition, suggesting that to do so would increase exposure to mercury vapor and result in more risks than benefits.
To maintain your fillings, you should follow good oral hygiene practices:
Call your dentist if:
Your dentist will take X-rays if he or she suspects that one of your fillings might be cracked or is “leaking” (when the sides of the filling don't fit tightly against the tooth, debris and saliva can seep down between the filling and the tooth, which leads to decay).
Tooth sensitivity after placement of a filling is fairly common. Your tooth may be sensitive to pressure, air, sweet foods, or temperature. Usually, the sensitivity goes away on its own within a few weeks. Until then, avoid the cause of the sensitivity. You usually don’t need to take a pain reliever.
Contact your dentist if the sensitivity doesn’t go away within two to four weeks or if your tooth is extremely sensitive. He or she may recommend using a desensitizing toothpaste, may apply a desensitizing agent to the tooth, or possibly suggest a root canal procedure.
There are several reasons why you might have pain after a dental filling. Each has a different cause.
There are three main reasons why dental fillings would need to be replaced.
New fillings that fall out are probably the result of improper cavity preparation, contamination of the preparation prior to placement of the restoration or a fracture of the restoration from bite or chewing trauma. Older restorations will generally be lost due to decay or fracturing of the remaining tooth.
It’s possible but fewer than 100 cases have ever been reported, according to the ADA. In these rare occasions, mercury or one of the metals used in an amalgam restoration is thought to trigger the allergic response. Symptoms of amalgam allergy are similar to those experienced in a typical skin allergy and include skin rashes and itching. If you've had an allergic reaction to an amalgam, it’s likely that you have a medical or family history of allergies to metals. Once an allergy is confirmed, another restorative material can be used.
Most dental insurance plans cover the cost of the composites up to the price of the silver filling, then you would need to pay the difference. It’s always best to contact your dental care insurance provider before procedures if you have questions or concerns about cost.
Last reviewed by a Cleveland Clinic medical professional on 02/23/2021.
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