Do me a favor—go to your bathroom mirror and shine a light at your front teeth. See anything that looks like hairline cracks? Those little pathways carved into your enamel are called craze lines. And if they’re driving you crazy, you’re not alone. It turns out, craze lines are an incredibly common and are more likely to form as we get older. But are they cause for concern?
Featured Experts
- Sonya Wintzell, DMD is a cosmetic dentist in Huntsville, AL
- Brian A. Klaich, DMD is a cosmetic dentist in Cranberry Township, PA
- Joe Kravitz, DDS is a cosmetic dentist in in Rockville, MA
- Joseph Field, DDS is a cosmetic dentist in Los Altos, CA
What Are Craze Lines?
“Craze lines are hairline cracks in the teeth, usually running vertically,” explains cosmetic dentist Sonya Wintzell, DMD. “Sometimes they are so small you may not notice them.”
While a crack in your tooth sounds horrifying, craze lines are superficial and impact the enamel, meaning they’re not an emergency. They rarely progress to serious cracks or damage, but they can have a significant impact on a person’s confidence.
“When a patient is not confident in their smile, they tend to hide it without even realizing,” explains Cranberry Township, PA cosmetic dentist Brian A. Klaich, DMD. “People train their lips and mouth to mask discrepancies in their smile subconsciously.”
That’s especially true when you realize that craze lines don’t go away. “They are irreversible,” Dr. Wintzell says. “Once you have them, you always have them.”
Causes of Craze Lines
“One cause of craze lines has to do with the expansion and contraction of teeth due to temperature changes in the mouth,” explains Rockville, MA cosmetic dentist Joe Kravitz, DMD. “Think of a resin cup, for example. When you first buy it, the material is clear and solid, but after many cycles of dishwashing in hot and cold water, you’ll see craze lines appear.”
These lines get more common as we age because they can occur from normal wear and tear. That said, they’re more likely to form with certain habits. “Excessive vertical teeth clenching, teeth grinding or bruxism, and even an unbalanced bite can all contribute to forming these kinds of lines,” Dr. Kravitz explains.
They also have a tendency to accumulate stain, which is why they can be more easily seen in people who drink coffee.
“While they rarely cause issues themselves, they can be a cosmetic concern,” Dr. Wintzell says.
“When we smile and feel confident in that smile, there are direct benefits to things like stress levels, cardiovascular health, mood, etc.,” explains Los Altos, CA cosmetic dentist Joseph Field, DDS. “And for many patients it’s the cosmetic issues that finally get them in the door to seek dental work. It isn’t until a problem is visible to other people that they’ll seek treatment.”
Beyond Cosmetic
While craze lines are primarily an aesthetic concern, that doesn’t mean they’re always asymptomatic. According to the University of Pennsylvania School of Dental Medicine, even very fine cracks in the enamel can result in increased sensitivity. That’s because the more delicate dentin below our protective enamel can be exposed through those super small cracks.
“There is also the chance of acidic damage to that dentin overtime,” Dr. Kravitz explains. “That could lead to pain and infection.”
The good news is, craze lines rarely go on to cause more serious damage in the tooth. “Craze lines rarely progress to deeper cracks without additional trauma,” Dr. Wintzell explains. “Being watchful for bad habits such as grinding your teeth or biting your fingernails or other hard objects can be helpful in preventing these form becoming an issue.”
Prevention and Treatment
Just like Dr. Wintzell explained, kicking bad habits now can help protect your teeth. “You should never treat your teeth as tools,” advises Dr. Field. “That will help you prevent serious damage and trauma.”
Of course, these lines aren’t always caused by direct trauma. You can do everything right and still see these kind of hairline cracks overtime. “Preventative treatments also include adjusting the bite, custom ceramic veneers, crowns and bite guards to help protect the tooth from otherwise unavoidable damage,” Dr. Kravitz says.
And while it’s true that craze lines are permanent, there are steps you can take at-home and in-office to improve their appearance or cover them entirely. “The appearance of craze lines can be sometimes minimized by whitening and professional whitening products,” Dr. Wintzell says. “They can also be easily covered up in-office using composite bonding which s noninvasive. Veneers are also an option if there are other cosmetic concerns behind craze lines.”
