Dental crowns are designed to restore both functionality and aesthetics to damaged or decayed teeth. However, if you’ve noticed the appearance of a black line around your crown, it can be a cause of stress and concern.

If you want to learn more about the potential reasons behind this strange quirk of dental crowns, continue reading. You’ll learn more about how crowns are made and finally understand those mysterious black lines.

What Is Causing the Black Lines?

While it could be a cavity or infection, the most likely cause has to do with how crowns are made. Many traditional dental crowns have a metal substructure where the porcelain is fused to a metal base.

This is done to cut costs as all-porcelain crowns are generally more expensive. Many times dentists can hide this metal under your gum tissue. However, sometimes situations arise where the metal could show as a black ring at your gumline.

What Causes the Metal in Dental Crowns to Become Exposed?

There are a few reasons why your crown metal may become exposed. Here are some of the more common issues:

Gum Recession

Receding gums expose the junction between the crown and the natural tooth, making the metal substructure more apparent. The resulting dark line can give the illusion of a gap between the crown and the gum.

Poor Margins

The crown may not have been properly fitted by your dentist. Imperfections in a crown’s margins (the space between the restorative material and the tooth structure) can create a gap.  This can lead to bacteria and debris accumulating in the gap, causing discoloration.

Decay or Infection

In some cases, the appearance of a black line may be a sign of underlying decay or infection. If left unaddressed, this can compromise the health of the tooth and the longevity of the crown.

What Should I Do If I See the Dark Lines?

Whatever the underlying cause of the dark lines on your crowns, you should see your dentist. You may be unable to properly diagnose the reasons for the line’s formation, but a professional can.

If the reason behind the discoloration is the crown itself, you may consider having it replaced with an all-porcelain version. If it’s decay, your dentist will be able to handle it by other means such as fillings.

While a black line around your dental crown may raise concerns, it’s important to see your dentist. They can perform a thorough exam and give you guidance about how to proceed. Identifying the cause early on can lead to quick, painless solutions, ensuring the continued health and aesthetics of your smile.

About the Practice

At Oyler Family Dentistry, their dental team is armed with the latest technology to solve all of your oral health issues. From simple fillings to dental crowns and other restorations, their experts can do it all. They pride themselves on the welcoming environment they’ve created in their office and the smiles of their patients when they finish their appointments. To schedule an appointment, call (812) 221-1014 or visit the website to explore all the services they provide.

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