A filling helps to restore a tooth damaged by decay back to its normal function and shape, and helps prevent further decay by eliminating areas where bacteria can enter the tooth. Your dentist will consider a number of factors when choosing which type of filling material is best for you; this includes the extent of the repair, whether you have allergies to certain dental materials, where in your mouth the filling is needed and the cost.
There are various types of fillings available including:
Composite Fillings – A composite resin filling is made from a mixture of plastic and fine glass particles and matches the colour of the tooth. Thus, composite fillings are used most often on front teeth or the visible parts of the tooth. Composite fillings bond directly to the tooth, reducing the amount of tooth structure that needs to be removed compared to an amalgam filling.
Amalgam Fillings – Amalgam fillings are made from a mixture of metals including mercury and silver, and thus do not match the colour of your teeth. This type of filling is used most often for fillings in the back teeth. These fillings are very strong and usually last at least ten years or longer.
Gold Fillings – Gold fillings are made from gold allow which is extremely durable. This type of filling lasts longer than any other type. Gold fillings do not match the natural colour of your teeth and are expensive. They usually cost six to ten times more than amalgam.
Ceramic Fillings – Ceramic fillings are made of porcelain and are tooth coloured, so they look natural. Ceramic fillings are more brittle than composite resin and can break but they are also more resistant to staining. Ceramic fillings are expensive, and can cost as much or more than gold fillings.
Glass Ionomer – Glass Ionomer fillings are made from acrylic and fluoroaluminosilicate, a component of glass. This type of filling is very strong and most often used in people with a lot of decay in the part of the tooth that extends below the gum. It is also used for filling baby teeth.
To help minimise the pain associated with getting a filling, your dentist may choose to administer a local anaesthetic, like Lignocaine. Next, your dentist will remove decay from the tooth, using a drill, laser or sometimes a very small hand instrument.
Once all the decay is removed, your dentist will shape the space to prepare it for the filling. Different types of fillings require different shaping procedures to make sure they will stay in place. Your dentist may put in a base or a liner inside the tooth to protect the tooth's pulp (where the nerves are).
A special light hardens certain types of fillings. With these fillings, your dentist will layer the material, stopping several times to shine a bright light on the resin. This cures (hardens) the material and makes it strong.
Finally, after the filling is placed, your dentist will use polishing burs to finish and polish the tooth surface.
After a filling procedure, there are a variety of side effects that can occur after the anaesthesia wears off. The tooth may be sensitive to pressure, cold air or liquids or sweet foods. Some people may experience numbness, tingling, and some minor pain around the injection site. These side effects often subside within a few hours of the procedure.
Sensitivity should decrease in one to two weeks. Until then, try to avoid anything that causes it. If your tooth is extremely sensitive or your sensitivity does not decrease after two weeks, contact your dentist's office for an appointment.
The most common reason for pain right after a filling is that the filling is too high; your dentist can adjust the filling by checking the occlusion (bite) of your teeth and removing some of the excess filling material to decrease the pain.
A rare type of discomfort after a filling is a very sharp shock that appears only when your teeth touch. This is called galvanic shock, and happens when two metals (one in the newly filled tooth and one in the occluding tooth) touch, producing an electric current in your mouth. This would happen, for example, if you had a new amalgam filling in a bottom tooth and had a gold crown in the tooth above it.