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The Weird Lines on my Crown | Dentist in Katy, TX

What are the black lines on my crown?

When you have a new crown placed, it looks pretty! Have you ever noticed a black line on crowns when people smile?

The black line on crowns can be caused by several factors:

  1. Using porcelain fused to metal (PFM) material
    • PFM crowns are made of two separate materials: the metal on the inside and the porcelain on the outside. It is the metal portion that is visible whenever the gum recedes.
  2. Gum recession away from the crown
    • Gums moving away from the crown will make the black line more noticeable.
  3. Staining
    • Staining can come from eating or drinking. The micro-space between the crown and the tooth can accumulate food pigments which cause extrinsic staining.
  4. Cavities underneath the crown
    • Food traps in the micro-space can cause cavities if you slack off on oral hygiene. A prolonged food trap will encourage decay on the micro-gap. Over time the gap becomes more noticeable as the decay grows. Neglecting the decay underneath a crown can result in losing the tooth! Therefore, it is important to brush and floss every day!

How do you get rid of the black line?

In most cases, the black line under the crown will need to be replaced with the new crown. Most of the time, the staining on the tooth needs to be removed by carefully trimming the stained part and having the laboratory make a new crown to fit your tooth. Although most crowns are made entirely of porcelain nowadays, it is important to consult with your dentist to see what works best for your circumstances.

If you happen to need a dentist to evaluate your crowns or need a general check-up, visit to inquire about an appointment!