Amalgam vs. Composite Fillings: Pros and Cons

What are amalgam fillings?

If you’ve never heard of amalgam fillings before, you will have seen them. Amalgam fillings are usually referred to as silver fillings and these are very common in older dental patients. In fact, dentists have used amalgam to treat cavities for around 150 years.

Amalgam fillings get their silver colour from the materials they are made from — usually silver, tin, copper, and mercury.

What are the key properties of amalgam fillings?

Amalgam fillings have been the go-to option of dentists for years. They are:

• Less expensive than composite fillings 
• Durable and long-lasting 
• Harden quickly makes them quick to fit in place 

What are the pros and cons of amalgam fillings?

There are lots of benefits to having silver amalgam fillings. These filings:

• Can last for over a decade with proper dental hygiene habits and care 
• Are strong and can easily fill large cavities within a tooth 
• Have a lower price point and are more affordable than composite filings 
• Harden quickly which makes treatment less stressful for anxious patients 

While there is nothing wrong with having amalgam fillings, there are a few reasons why dentists may prefer a composite filling instead.

• Amalgam fillings are very noticeable even when fitted onto the back teeth. 
• Patients with metal allergies may have a bad reaction to the metals. 
• Amalgam fillings sometimes require more of the tooth structure to be removed. 
• Amalgam fillings expand and contract with exposure to some temperatures. This can cause fractures in the tooth. 
• Amalgam fillings are made with 50% mercury. While this is generally low enough not to cause toxicity, mercury is still a toxic material. 

What are the key properties of composite fillings?

Composite fillings blend in with the colour of the tooth and are made from a polymer-based resin that is free from mercury.

• They are often used as a long-term solution for small and medium filings 
• They may not be an appropriate long-term solution for very large cavities. Porcelain fillings or a full crown are sometimes used instead. 

What are the pros and cons of composite fillings?

• Composite resin does not last as long as amalgam and has a shelf life of around 5 years. 
• They are usually more expensive than amalgam fillings. 
• They can take longer to fit in the mouth than amalgam fillings as the composite resin is placed in layers into the mouth. 

These might all sound like good reasons not to get a composite filing, but there are a few major reasons why some dentists prefer composite.

• Composite does not expand or change in size and won’t cause teeth to crack.  
• They are virtually undetectable. Composite blends in with the colour of your tooth. 
• Dentists don’t have to remove as much of the tooth as composite fillings bond to the tooth. This means the tooth is stronger as it has more structure to provide support.   
• Composite resin is completely nontoxic. 

At Dental Gentle we prefer to use composite fillings as they are safer, non-toxic, and won’t compromise the structural integrity of the surrounding tooth. You also won’t have to worry about your fillings being visible when you open your mouth.

Need a checkup? Book an appointment at Gentle Dental today.