If you have metal fillings, sometimes you will have the bad experience that a tooth with a large metal filling will crack. When this happens, you need to repair or replace that tooth.

But what about your other metal fillings? Should you take this opportunity to replace them, too as part of a full mouth rejuvenation? It might be a good idea, but you should understand why if you want to make a good decision.

Is It Time to Replace Metal Fillings

Why Metal Fillings Can Crack Teeth

Metal amalgam fillings have been used for a long time, but they are actually not a good solution for repairing your teeth. Even if we neglect the issue of toxic mercury in these fillings, they aren’t good repairs materials.

One of the biggest problems with metal amalgam fillings is that they have a different thermal expansion rate than your natural tooth enamel. This means that they expand more dramatically when exposed to heat and contract more dramatically when exposed to cold. And every day we are exposing our teeth to dramatic changes in temperature. Drink a hot cup of coffee and your filling wants to expand, so it puts pressure on  your natural tooth. Drink a cup of ice water, and your filling will shrink so it’s no longer filling the hole it sits in (more on this later).

This repeated cycle of expansion and contraction stresses your tooth enamel. It causes tiny cracks in the enamel. When you bite, chew, and clench your teeth, you put stress on the enamel that can make these cracks grow until, eventually, the tooth splits apart.

Tiny cracks are all but inevitable with metal amalgam fillings. But whether these turn into a failed tooth depends on other factors.

How Large Are Your Fillings?

One of the biggest factors in leading to cracked teeth is the size of the filling. Larger fillings want to expand more with temperature changes, which means there’s more force on your tooth enamel.

If you have other fillings as large as or larger than the one that caused a tooth to crack, seriously consider replacing those fillings.

Secondary Decay

Remember that we mentioned your fillings shrink when exposed to cold? With significant temperature changes, this can mean that your cavity isn’t completely filled any more. When that happens, food, drink, and bacteria can slip in alongside a filling. And they can turn that area into their new home. The acid they produce can enlarge the space around the filling, causing what we call secondary decay around the filling.

The presence of secondary decay around a filling is a definite reason to replace your metal amalgam fillings. We can perform an exam and help you identify where this is happening so you know which fillings truly need to be replaced.


Another problem with metal amalgam fillings is that they aren’t great insulators. Instead, they conduct heat and cold deep into your tooth, near the nerve. If you have amalgam fillings, they can make your teeth extra sensitive to heat and cold.

If you’re experiencing tooth sensitivity, it’s a good idea to replace the fillings responsible.


And, of course, we have to consider the appearance of these old fillings. While these fillings may be in the back of your mouth, they may be highly visible, especially when you talk.

And these fillings may have started out silver, but it doesn’t take long for them to turn black. When they do, they look as bad as–or even worse than–untreated cavities.

If the appearance of old metal amalgam fillings makes you self-conscious, then you should take this opportunity to do what you can to restore a smile that you’ll feel comfortable and confident with.

Are You Looking to Replace Metal Fillings?

If you are looking to replace your metal amalgam fillings in Savannah, GA, we can help. Please call (912) 234-8282 today for an appointment with a cosmetic dentist at Beyond Exceptional Dentistry.