What are NHS fillings and crowns made of?

Fillings and crowns available on the NHS can be made of several different materials.

Ask your dentist what material they recommend, as some will be more suitable than others.


Fillings are used to repair a cavity in your tooth caused by decay. The most common type of filling is dental amalgam, made from a mixture of mercury and different metals. Dental amalgam fillings are often used on your back teeth as they are hard-wearing.

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

Fillings on the NHS can be made of:

  • amalgam (silver-coloured)  a mixture of metals including mercury, silver, tin, and copper
  • composite (tooth-coloured)  powdered glass and ceramic added to a resin base; they're not as hard-wearing as amalgam fillings 
  • glass ionomer (tooth-coloured)  powdered glass, which reacts chemically with your tooth and bonds to it, but it is weak so is only used on baby (first) teeth or around the sides of teeth


A crown is a type of cap that completely covers a real tooth. Crowns on the NHS can be made of:

  • alloys (mix of metals) containing not less than a third of fine gold, platinum, or palladium
  • alloys containing stainless steel, cobalt chromium or nickel chromium  
  • porcelain
  • porcelain bonded to precious metals
  • alloys bonded to wrought platinum coping
  • ceramic
  • glass
  • gold alloy crowns

Prefabricated crowns (crowns made ahead of time) are made from plastic and metals. These are used temporarily until a permanent crown can be fitted.  

Read the answers to more questions about dental health.

Further information:

Page last reviewed: 02/02/2015

Next review due: 02/02/2018