A filling is something that most people will have undergone at some point in their lives. They are a form of treatment for tooth decay or to restore a damaged tooth. The most popular type of filling is the Composite (white filling) filling.

There is the standard filling and then there are cosmetic fillings which are performed for aesthetic reasons. These are known as onlays and inlays. 

Find out more about these in Inlays & Onlays.  

Another type of filling is the direct white filling which is also discussed separately. 
 

A filling is the name of a dental procedure in which a material such as silver amalgam or a composite (white) filling is used to treat a decayed tooth. This material is inserted into the tooth where it then prevents the further spread of decay or repairs any damage.

This treatment stops the decay from spreading into the root where it will cause a serious infection, e.g. an abscess. This also removes the need for a tooth extraction. 

The silver amalgam filling is the traditional type of filling which is composed of various metals such as copper, tin and mercury. This combination helps to retain the normal function of the tooth. 

The composite white filling is a synthetic combination of acrylic resin and glass which has a white colour thereby enabling it to match the colour of the tooth. This is also chosen for aesthetic reasons as many people prefer to have fillings which match the rest of their teeth rather than the distinctive silver filling.   
 

The main advantage of silver amalgam fillings is their durability. These fillings can last for more than 10 years or more compared to other types of fillings. 

Composite white fillings have a natural colour which is similar to the colour of your natural teeth and so blends it well with them. Plus there have been issues raised about the safety of silver amalgam fillings due to their mercury content which has prompted some people to switch to composite fillings instead. 

In regard to inlays and onlays: these fillings are less extensive than a normal filling, are easy to care for and long lasting. 
 

Silver amalgam fillings have attracted some negative press commentary which is related to their use of mercury. There have been reports of people developing a health problem which is linked to mercury poisoning although the risk is considered very small. 

The alternative is to choose a composite white filling or inlays and onlays. 

Composite white fillings come with a range of benefits but they have their disadvantages as well. These are discussed further in the direct white fillings section. 

The disadvantages of inlays and onlays are discussed within their own section.
 

For both the silver amalgam and composite white fillings the procedure involves the drilling of a small hole within the affected tooth which is then packed with the filling. 

The only difference is that the dentist will give the composite filling a final polish to ensure that it has that clean, white look and fits in with the rest of your teeth. 

There is a different procedure for inlays & onlays which is covered in greater detail. 

 All ceramic inlays and onlays 

These are chosen for aesthetic reasons. They are preferred to the traditional amalgam filling and many people choose to replace their fillings with the natural coloured inlays and onlays. 

There is another option: composite inlays and onlays which are discussed in another section. 
 

These inlays and onlays are made from a tough, ceramic material which resembles the natural colour of your own teeth and is extremely attractive to view. 

An inlay or onlay is a type of material which is placed inside or over the surface of a decayed or damaged tooth and are seen as a good alternative to a crown. They are made from a variety of materials such as gold or ceramic and cover the top surface of a tooth. 

This section discussed the all ceramic or metal free type of inlay and onlay. 
 

The main benefit is that they fit in well with the rest of your teeth. The material used is ‘tooth coloured’  and has a realistic appearance which is good news from a cosmetic point of view.

Many people choose this type of inlay and/or onlay as a replacement for their amalgam fillings. They find this type of filling ugly looking and unsightly and prefer to have a type of filling which is hard to distinguish from the rest of their teeth.

This sometimes form part of an overall ‘smile makeover’ in which various procedures are performed to improve the look of the teeth and as a confidence boost. 

There is no risk of the inlays and onlays becoming discoloured over time. They are easy to clean as part of a daily dental routine and provide extra support for a tooth. 

Ceramic is strong and durable but because it is a rigid material it is also at risk of a fracture. If too much pressure is put on the inlay/onlay, for example, biting on an item of hard food then it is liable to break. 

It can also cause the tooth to become worn down over time. 

This procedure is the same for all types of inlays and onlays. It involves two visits to the dentist as opposed to the single visit undertaken for a standard filling. 

The dentist will explain the procedure to you and will discuss the various types of materials used in inlays and onlays. These include gold, ceramic and composite resin. 

The dentist will examine the affected tooth before taking an impression of this using a putty filled mould. This requires you to bite into the dental putty which leaves an imprint of the tooth which will be used to create the inlay or onlay. 

The inlay or onlay is fabricated at a dental laboratory.

Your affected tooth will be covered with a temporary inlay or onlay (known as a ‘temp’) during this time. 

On your second visit the temp is removed and replaced with your new inlay or onlay. This is secured in place with dental cement before being given a final polish.