Readers ask, we answer: 

Cracks and craze lines 

Michael asks: “When I look in the mirror, I notice thin vertical lines on my front teeth. Is this something I should be worried about?”

Hi, Michael,

Those vertical lines are actually small, hairline cracks in the enamel of your teeth. Called craze lines, they’re common and often develop as you grow older. Craze lines can appear translucent, gray, yellow or brown.

There’s no need to be concerned about the appearance of craze lines, but they may increase the amount of visible staining on your teeth. That’s why they’re more visible if you drink dark beverages or use tobacco products.

Craze lines are generally caused by:

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    Everyday wear and tear

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    Teeth grinding or clenching (bruxism)

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    Uneven bite

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    Nail biting

Unlike cracked teeth, which occur when there’s actually a fracture in the tooth, craze lines are merely surface cracks. In addition, craze lines rarely require treatment to preserve the tooth, and they don’t cause pain, swelling or sensitivity.

While craze lines are largely a harmless cosmetic concern, it’s still important to consult your dentist to find the cause and to make sure they’re not more serious. If your craze lines are caused by bruxism or gum disease, your dentist can treat the underlying causes.

Want to minimize the appearance of craze lines? Avoid using tobacco products and drinking dark-colored beverages like coffee, red wine and black tea, all of which can darken craze lines. Don’t chew on ice or other hard items. And remember: If it’s not food, don’t bite it, as you can worsen craze lines and damage teeth.

If you’re concerned about the appearance of craze lines, your dentist may recommend teeth whitening or cosmetic restorations such as crowns or veneers. These procedures may not be covered by your dental plan, so always check your plan details.

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