To treat a cavity, the decayed portion of the tooth is removed and then the area is “filled” with a material of your choice after close consultation with us. In addition, fillings are 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 area around the tooth to be filled is anesthetized (numbed) with a local anesthetic. Then, a drill, air abrasion instrument, or a laser can be used to remove the decayed area.
Next, a probe is used to test the area during the decay removal process to determine if all the decay has been removed. Once the decay has been removed, the space is prepared for the filling by cleaning the cavity of bacteria and debris. If the decay is near the root, a liner made of glass ionomer, composite resin, or other material may be used to protect the nerve. Generally, after the filling is placed, a finish and polish is applied.
Several additional steps are required for tooth-colored fillings. After the decay is removed and the area is cleaned, the tooth-colored material is applied in layers. Next, a special light that “cures” or hardens each layer is applied. When the multi-layering process is completed, the composite material will be shaped to the desired result, any excess material will be trimmed, and the final restoration will be polished.
What Types of Filling Materials Are Available?
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 glass materials called composite resin fillings. The location and extent of the decay, cost of filling material, patients’ insurance coverage, and Dr. Dillon’s recommendation assist in determining the type of filling that will best address your needs.
Cast Gold Fillings
Advantages of cast gold fillings:
Durability – lasts at least 10 to 15 years, but usually longer and sometimes a lifetime
Strength – can withstand chewing forces
It does not corrode like silver fillings that turn black with age
Aesthetics – some patients find gold more pleasing to the eye than silver, amalgam fillings
Disadvantages of cast gold fillings:
Expense – gold cast fillings are more than other materials; up to 10 times higher than cost of amalgam filings
Additional office visits – requires at least two office visits to place
Galvanic shock – a gold filling placed immediately next to a silver, amalgam filling can cause a sharp pain (galvanic shock) to occur. The interaction between the metals and saliva causes an electric current to occur, however, this is a rare occurrence
Aesthetics – most patients do not like any “metallic” fillings
Silver Fillings (Amalgams)
Advantages of silver fillings:
Durability – silver fillings last at least 10 to 15 years and usually outlasts composite fillings
Strength – can withstand chewing forces
Expense – is less expensive than composite fillings
Disadvantages of silver fillings:
Poor aesthetics – silver fillings do not 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 grey 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 may experience a wider degree of expansion and contraction and lead to a higher incidence of cracks and fractures in comparison with other materials.
Allergic reactions – a small percentage (1%), are allergic to the mercury present in amalgam restorations
Advantages of composites:
Aesthetics – the shade/color of the composite fillings can be closely matched to the color of existing teeth; is particularly well suited for use in front teeth or visible parts of a patient’s smile
Bonding to tooth structure – composite fillings actually chemically bond to tooth structure in a micro-retentive fashion, 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 – sometimes less tooth structure needs to be removed compared with amalgams when removing decay and preparing for the filling
Disadvantages of composites:
Lack of durability – composite fillings wear out sooner than amalgams (lasting at least 5 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
Expense – composite fillings can cost up to twice the cost of amalgams