A Filling is an artificial material used to replace parts of the tooth that have been damaged/dissolved by tooth decay or have fractured.
Often a tooth will need local anaesthetic to deaden any pain before it can be worked on. Sometimes for minor (shallow) fillings no anaesthetic may be needed. When the tooth is numb, it will often be isolated with cotton rolls or a rubber dam (a sheet of rubber which covers all the other teeth except the ones your Dentist is working on.)
The decayed part of the tooth can then be removed using small drills to clean out the decay. Fine hand instruments, like small spoons may also be used. Often a small amount of good tooth has to be removed to allow access to the diseased part, or to help hold in the filling. Your Dentist will always keep this to a minimum.
For some larger fillings there may be a need to place small metal screws (pins) into the tooth to help hold the filling on. A very fine hole is drilled and then the pin is screwed into place to act as a foundation for the filling.
Many teeth require an additional layer(s) of material between the filling and the tooth. This base often contains soothing materials to protect the nerve of the tooth. It also acts to insulate the nerve from any heat that may come via the Filling from hot or cold food. A varnish layer may also be painted on to provide a better seal and stop any bacteria getting into the cavity.
Fillings which replace a side wall of a tooth will often need a band placed around them, temporarily, to allow the filling to be placed without joining it to the adjacent tooth. The band can be a very thin metal strip or a fine strip of plastic, depending on the type of filling. The band may be held in place with a small tightening arm and or very small wedges of soft wood or plastic. All of this is removed when the filling has started to set.
Why do I need this?
The treatment for decay involves removing all the diseased and infected decay. After this has been completed a hole is left in the tooth and this hole needs to be sealed to protect the remaining tooth from further decay. The deeper parts of the tooth are more sensitive (as they are closer to the nerve) and filling over the top acts as a protective barrier. The missing part of the tooth also needs to be replaced to allow it to function for eating and speaking. Chipped or broken teeth that are not filled can also be cosmetically unattractive.
Types of fillings
Metallic fillings (amalgam) are mixed and then squeezed into the hole, before being further pressed into place with small hand instruments to ensure there are no gaps. Tooth- coloured fillings (composite resins and glass ionomer cements) may set by themselves after a short period or may be set a little bit at a time using a very bright light, which is placed near the filling. Before the filling is fully set your Dentist will adjust the shape of the filling to best match the shape of the original tooth. Further adjustments may be made by carving the filling with fine hand instruments and with small sandpaper discs in drills. To determine how much the filling needs to be shaped to become level with the other teeth your Dentist may ask you to gently bite on some special paper strips which lightly mark the teeth to indicate the points where the teeth touch. Fine strips like sandpaper may be used to polish between the teeth. Some fillings can only be fully polished after being allowed to set for some days.
Some fillings have a double set. They look hard but may not reach full strength for many hours. Ask your Dentist how long you should wait to eat or drink after having a Filling. Eating or drinking on a Filling that has not set properly may damage the Filling which may then require further treatment.
As with all dental conditions, your Dentist should be consulted. There are many different types of Fillings. Your Dentist will diagnose and treat your particular problem.