When tooth decay or other damage causes a cavity or crack in a tooth, a filling is usually the recommended treatment.
The dentist usually uses a drill to remove the decayed section ready for the hole to be filled, usually with amalgam or white filling material.
What steps are involved in filling a tooth?
First, the dentist will numb the area around the tooth to be filled with a local anaesthetic. Next, a drill, air abrasion instrument or laser will be used to remove the decayed area. The choice of instrument depends on the individual dentist's experience, 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 coloured fillings and are as follows. After your dentist has removed the decay and cleaned the area, the tooth-coloured material is applied in layers. Next, a special light that "cures" or hardens each layer is applied. When the multi-layering 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 gold, porcelain, silver amalgam (which consists of mercury mixed with silver, tin, zinc and copper) or tooth coloured, plastic and glass materials called composite resin fillings. The location and extent of the decay, cost of filling material, and your dentist'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, usually longer; doesn't corrode
- Strength. Can withstand chewing forces
- 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 surgery visits. Requires at least two visits to place
- Galvanic shock. A gold filling placed immediately next to a silver or amalgam filling can cause a sharp pain (galvanic shock) to occur. The interaction between the metals and saliva causes an electric current to occur. It is, however, a rare occurrence
- Aesthetics. Most patients don't like any "coloured" fillings