Dental crowns are designed to protect damaged teeth while restoring the appearance of your smile. They’re durable, long-lasting, and can look incredibly natural. However, if you’ve noticed a dark or black line appearing near the gumline of one of your crowned teeth, you may be wondering whether something is wrong.

In many cases, the black line isn’t a sign of a dental emergency—but it is a clue about the type of crown you have. Here’s why it happens and what can be done to improve your smile.