A filling is needed in a tooth when either decay is present (either seen directly or via a dental radiograph), a tooth has been chipped or a previous filling has broken.

Fillings are also used to repair cracked or broken teeth and teeth that have been worn down from actions such as tooth grinding, accidents or nail biting.

To treat a hole or decayed portion of a tooth we need to remove the decayed portion then “fill” the tooth.

Although a “filled” tooth will never be as structurally sound as the original, it is important that the the decay is repaired as soon as possible to prevent the decayed area becoming larger.

There are often different choices of material to fill a tooth with and each material comes with a series of “pro’s and con’s”.  We will often advise you on which material we feel is best for you.


amalgam versus white fillings


One of the most established filling materials is dental amalgam, made from a mixture of different metals. Dental amalgam fillings are hard-wearing so are often used on your back teeth.

There are a number of articles on the internet about the alleged toxic properties of amalgam. Although amalgam fillings can release low levels of mercury vapour, particularly when they are put in or removed, there is no evidence that exposure to mercury from amalgam fillings has any harmful effects on health. 

If you need a filling for one of your front teeth, we will always place a tooth-coloured (white) filling.


We will offer you the type of filling most appropriate for your clinical (medical) needs. For example, if you need a filling for one of your front teeth, your dentist may suggest a tooth-coloured (white) filling, but the use of tooth-coloured fillings on back teeth is considered purely cosmetic.

Fillings available can be made of:

  • amalgam (silver-coloured) – a mixture of metals, including mercury, silver, tin and copper 
  • composite (tooth-coloured) – made of resin and glass mixture 
  • glass ionomer (tooth-coloured) – powdered glass, which forms a chemical bond with your tooth and may release fluoride that helps to prevent further decay
  • ceramics (often referred to as an inlay)

What Are The Differences Between Fillings??

Amalgam (silver) fillings


  1. Durable – can last 10-15years, usually outlast composite fillings
  2. Strength – very resistant to chewing forces
  3. Cost – less expensive than composite fillings
  1. Poor aesthetics – not same colour as tooth and may stain the remaining tooth material
  2. Allergic reaction – approximately 1% of people may be allergic to this material

Tooth coloured composite fillings

  1. Aesthetics- the colour of the composite can be closely matched to the colour of existing teeth.
  2. Versatility- can be moulded to change existing shape or “build-up” teeth.
  3. Minimal tooth preparation- sometimes less tooth structure needs to be removed compared to amalgam when preparing tooth for filling.
  1. Lack of durability- composite fillings wear out sooner than amalgams.
  2. Increased chair time -this can be a more technical procedure to place than that of metal fillings.
  3. Chipping – depending on location, composite materials can chip off the tooth.
  4. Expense
  5. Can stain and become discoloured over time.

In addition to amalgam and composite (white) fillings, two other tooth-coloured fillings exist, ceramics and glass ionomers.

Glass ionomer

This material is most commonly used for fillings in children and in teeth that have decay under the gum line or have a poor prognosis. Glass ionomers release fluoride which can help protect the tooth from further decay.  however this material is weaker than both amalgam and composite filling materials so is more susceptible to wear.


This is usually a two stage process with the filling be made in a dental laboratory.   During the first visit the decay and/or old filling is removed and and impression is taken of the ‘hole’ which sent to the dental laboratory.  a temporary filling will be placed to protect the tooth whilst the permanent restoration is being made.  At the second visit (usually 2 weeks later) the temporary filling is removed and the permanent restoration cemented into place.

Ceramics are a tooth coloured material which are hard wearing.  They are expected to last around 15 years but are expensive to make and fit.  The cost of a ceramic filling, or “inlay” is approximately £400.