Dental fillings

What is a dental filling? 

Fillings are placed in a tooth following removal of decay.  They are also used to repair broken or worn teeth (e.g. caused by erosion or tooth grinding).  Decay that is left untreated can progress to the nerve of the tooth, causing pain and/or infection. 

Types of filling 

The location and extent of decay and your dentist's recommendation will help in deciding the type of filling which is best for you. 

Possible complication of dental fillings 

1. Tooth sensitivity following placement of a filling – this should normally resolve within a few weeks.  Contact the clinic if the sensitivity does not subside within 4 weeks. 
2. Toothache – if the decay was very deep and close to the nerve, a toothache may indicate the tooth is no longer healthy and may require further treatment. 
3. Deterioration of fillings – most fillings will need to be replaced at some time.  Regular check-ups will help the dentist to identify deteriorating fillings. 

Silver (Amalgam) fillings 

Amalgam fillings contain mercury mixed with other metals such as silver, copper, tin and zinc to form a stable alloy.  Amalgam has been in use for over 150 years. 

The safety of dental amalgam is reviewed every few years by the Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) on behalf of the European Commission (EC).  The SCENIHR concludes that, based on current scientific evidence, neither dental amalgam nor alternative materials are harmful to the health of the general population.  

Following European Union Regulations, environmentally regarding the use and disposal of mercury, from 1 July 2018, dental amalgam shall not be used for dental treatment of:  

• pregnant or breastfeeding women  

• children under 15 years  

• deciduous teeth (baby teeth or first teeth) except when deemed strictly necessary by the dental practitioner based on the specific medical needs of the patient 

Advantages of Amalgam 

• durability – amalgam fillings usually outlast composite/glass ionomer fillings
• strength – more hard wearing than composite/glass ionomer

Disadvantages of Amalgam 

• silver colour
• more extensive tooth preparation may be required
• does not stick (bond) to the tooth

Composite fillings

Composite fillings are made from powdered glass, quartz, silica or other ceramic particles added to a resin base. 

Advantages of composite 

• tooth coloured 

• bonds to the tooth  

• can be used to repair broken or worn teeth 

• less tooth preparation may be required 

Disadvantages of composite 

• less durable than amalgam fillings
• lower strength than amalgam, particularly on the biting surfaces of teeth 

• requires a longer time to have the filling placed with careful moisture control 

• composite fillings can stain over time 

Glass Ionomer fillings 

Glass ionomer is made of a polyacrylic acid and silicate glass powder. 

Advantages of glass Ionomer

• bonds to the tooth 

• tooth coloured, though a limited shade selection 

Disadvantage of glass Ionomer

• weaker than composite 

• glass ionomer fillings can stain over time 

How do I care for my fillings?

To maintain fillings, you should follow good oral hygiene practices including: 

• eating a healthy diet - limiting sugary and acidic foods and drinks to meal times
• brush your teeth twice daily with fluoride toothpaste – spit out the toothpaste and don't rinse your mouth
• clean between your teeth using floss or an interdental brush.  Speak to your dentist for further advice
• speak to your dentist for further advice on using a daily fluoride containing mouthwash
• visit your dentist regularly