Amalgams Vs Composites: Which is The Better Choice?

When people think of fillings, they think of the silver, metal fillings that have been around for the last 150 years. However, with the new advancements made in dentistry, traditional amalgam fillings are no longer the only choice available, and today many dental offices also provide composite resin. We discuss both to help give you a better understanding.

Why Dental Fillings Are Important

Before diving into the pros and cons of the types of materials used for dental fillings, let’s discuss what a filling is, and why it is needed to maintain your oral health. Dental fillings are designed to replace decay in your tooth and restore a tooth’s appearance, strength, and structural integrity.

Although dental enamel is the strongest tissue in your body, it is still susceptible to bacteria. Bacteria feed on sugars and starches and releases an acid byproduct, which softens enamel, allowing even more bacteria to invade and break down your tooth and cause cavities. If left untreated, the bacteria can continue invading deeper into the tooth and reach the nerve of the tooth, which results in pain, infection, and the need for a root canal or tooth extraction.

When the cavity is small, your tooth can still be restored with a filling. Your dentist will remove bacteria and decay and thoroughly clean the tooth, before placing a dental filling into the prepared hole. This helps restore your tooth back to its original shape and function.

Pros and Cons of Amalgam Fillings

Commonly known as silver fillings, amalgam fillings are made from a variety of metals, such as silver, mercury, zinc, and copper. Compared to composite resin, this type of filling is more affordable and when properly cared for, can last up to 15 years. Because of the metal alloy used, amalgam fillings offer stronger resistance to wear, making them a superior choice for back teeth or larger areas of decay.

However, amalgam fillings have developed a bad reputation due to the mercury used, as some patients are particularly sensitive or allergic to it. Another downside is its appearance. Silver fillings are more noticeable, especially when you are laughing or smiling widely. Over time, amalgam filling can also stain the appearance of the entire tooth, making it appear greyish and less aesthetic. Lastly, large amalgam fillings can create stresses and fracture lines that can lead to large cracks in teeth.

Pros and Cons of Composite Resin Fillings

Composite fillings, also known as tooth-coloured fillings, are made from a combination of plastic and ceramic compounds. It comes in a range of tooth shades, which allows the dentist to blend the filling much better with your tooth, giving it a more natural appearance. It also requires less enamel removal and tooth preparation, allowing you to maintain as much of your natural tooth structure as possible.

The cons to composite fillings are its technique sensitivity and longevity. Composite resin fillings are more difficult to place than amalgam fillings as they are more moisture sensitive. Older versions of composite have been though to be not as resistant to wear as amalgam. However, as newer bonding techniques and stronger versions have been produced, composite resin fillings have proven to be very durable.

What is the right choice for me?

In the last 30 years, there has been a shift away from amalgam towards composite resin fillings. This shift has been brought about due to concerns about mercury toxicity as well as the general trend towards more aesthetic, tooth coloured fillings.  In practice, most patients prefer tooth coloured fillings and are reluctant to accept amalgams.

At Dental Designs we make every effort to fill cavities with tooth coloured composite resin, as we believe that this filling option is the best because it is safer, less noticeable, keeps your teeth stronger and also has good longevity.  In cases when a cavity is too large or located on a back tooth that encounters a lot of forces, we may recommend other treatment options such as an inlay or a dental crown.

This article was written by Dr Jo Ann Wong. 

References:

1. Is It the End Of the Road For Dental Amalgam? A Critical Review
   Arvind Shenoy - (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2813106/)
2. A Controlled Clinical Study Of Amalgam Restorations: Survival, Failures, and Causes Of Failure
   Letzel H;van 't Hof MA;Vrijhoef MM;Marshall GW;Marshall SJ; - (https://pubmed.ncbi.nlm.nih.gov/2606273/)

3. Longevity Of Restorations in Posterior Teeth and Reasons For Failure
4. Hickel J; - (https://pubmed.ncbi.nlm.nih.gov/11317384/)
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7. Microleakage Of Composite Fillings in Er,cr:ysgg Laser‐prepared Class Ii Cavities
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