Amalgam vs. Composite Fillings

Why More Dentists are Offering Alternatives to Metal Fillings

Many dentists are beginning to offer more composite (white) fillings compared to the traditional amalgam (metal) fillings, but why? Both types have their pros and cons and it really depends on the treatment plan and the individual patient’s dental needs and goals. However, one of the main reasons composite fillings are becoming more popular is because of flexibility.

Filling Placement

With composite fillings, doctors can insert a composite filling into the cavity that is forming regardless of size. However, with metal fillings, there’s a size requirement before it can be installed and begin preserving natural tooth structure. These fillings are held in place by the shape of the cavity. Doctors will often recommend metal fillings when the filling placement area needs to remain dry or needs to be placed below the gum line.

Composite fillings are comprised of plastic resin that is “glued” in place to the tooth. The substance is soft at first but cures to full strength after short exposure to the blue range of the light spectrum. These fillings can be very small and are adaptable to the shape of the cavity. However, these need to be applied to a dry area so the bond can set. That said, they are not recommended for cavities below the gum line where the bond will not fully set.


A downside with amalgam fillings is that you only get one color. Besides not being flexible and not matching your smile, over time the filling will begin to percolate into the tooth and gradually darken it. With composite fillings, they come in a wide variety of colors to match your specific smile and will not cause any tooth discoloration over time.


Here is where amalgam fillings outpace its composite counterpart. Composite fillings are softer in nature, which leads to them wearing down much more quickly in people who grind their teeth. Also, they need to be kept clean and require regular brushing and flossing, as they tend to develop a cavity along the edges if proper hygiene isn’t performed. That is not to say having amalgam fillings is a substitute for good dental hygiene, but rather it’s more forgiving than composites.

All in all, amalgam fillings can last 20+ years, while composite can last 10+ years with much more upkeep required.


While technology in the last decade as allowed for composite fillings to be placed in molars, they are usually reserved for the six front teeth. They are aesthetically pleasing and placed on the most visible teeth, which increases the cost despite its reduced longevity when compared to amalgam fillings.


Much of the concern over amalgam fillings stems from the use of mercury. However, when this element is combined with the other metals such as copper, silver, and tin, it is rendered harmless. The American Dental Association maintains that amalgam fillings are safe to use and the amount mercury released in the mouth while chewing or grinding is negligible and poses no threat to your health.

Which Filling Material Should I Choose?

As with most health-related questions, it’s a decision you and your doctor must make together. If you’re looking for a low-cost way to have a cavity filled that can last 20+ years, amalgam fillings might be the best route for you. If you want to preserve your smile with fillings that match your teeth color and accept the fact that they do not last as long as their metal counterparts, composite might be the best choice for you.
Dobbs & Adkins, DMD, LLC is here to help you answer any dental question you might have. As with all procedures we recommend, we will help educate you on all possible options so you can make informed decisions about your dental health. Call us today (205) 655-4300 to schedule an appointment!