What Are Craze Lines & What To Do About Them

What Are Craze Lines & What To Do About Them

 Whitney DiFoggio BS, RDH
Written by Whitney DiFoggio BS, RDH
Medical Reviewed on Nov 8, 2022
byDr. Matthew Hannan DDS
🔬 Evidence Based
What Are Craze Lines & What To Do About Them

Craze lines are tiny, hairline cracks on teeth that run vertically (up and down) across the surface. Most of the craze lines in teeth are only visible up close. They can look like cracks or white lines on teeth, or even have a grey, blue, or brown shade to them.If they start to accumulate stain (since particles can seep down inside of the cracks in your teeth) they will be more noticeable. Lighting can also play a factor in how visible they are.

The good news is that these fine white lines on teeth usually aren’t something to worry about in a structural sense. Craze lines tend to be more of an aesthetic, superficial issue.

What Are Craze Lines?

Craze lines are superficial cracks on the outer surface of your tooth enamel. They run vertically (up and down), creating tiny, vertical lines on teeth that you can see when you look closely. There could be one or several of them. Rest assured, they are completely common, especially as you get older.

Some people only have one or two craze lines while others have multiple white lines on teeth throughout their mouth. The ones on your front teeth tend to be the most noticeable because you see those teeth more often. And since tiny cracks in the enamel will accumulate stain particles more easily, you might notice your craze lines more over time as they become discolored. 

Unlike large cracks in teeth, craze lines aren’t a major cause for alarm. Aside from causing cosmetic problems, you don’t have to run off to the dentist to get a root canal or crown anytime soon. But you will want to monitor them over time to make sure the superficial lines on the tooth enamel don’t evolve into deeper fractures.

Can A Craze Lines Turn Into Cracked Teeth?

Any time you see tiny little white lines on teeth, especially if there are several of them, they tend to be superficial in nature. But that point is definitely a weaker spot in your tooth than all of the tooth enamel around it. There’s always a risk it could get worse. 

You could compare it to an old porcelain plate. Even though your dish is still intact, you might see multiple tiny little cracks across the surface in certain areas. That doesn’t mean you can’t use it or that it’s going to break if you’re handling it properly, but it does indicate that the porcelain is getting older and starting to show signs of its age.

It’s basically the same thing when it comes to your tooth enamel. Those tiny lines on teeth are more superficial than they are structural. But if you were to continue bad habits such as chewing on pens or your fingernails, you could be exerting too much stress on them. Areas that are already weak could break right off. Although craze lines don’t always evolve into deep cracks, the potential is there if you’re applying too much atypical force on your teeth.

Causes of Craze Lines

Here’s the part you’re probably not going to like. Most of the craze lines on teeth are caused by two things: age and bad habits. 

The older you get, the more likely you are to start seeing visible lines in teeth when you smile. Just like that piece of china you inherited from your grandmother, the older it is, the more likely you are to see some surface cracks.

However, some factors can make certain people more prone to cracks or lines on teeth enamel. Common causes of craze lines:

  • Nail-biting
  • Chewing on foreign objects (pens, pencils, hairpins, etc.)
  • Clenching and grinding your teeth
  • Teeth grinding (bruxism) caused by sleep apnea
  • Using your front teeth to chew or bite hard foods (nuts, seeds, etc.)

If you already have craze lines, some habits can make the white lines on teeth more noticeable. Such as drinking a lot of coffee or other dark liquids. As the stain particles seep down and around the lines in teeth, they become more prominent in your smile. 

Can Craze Lines Disappear?

Unfortunately, once you have surface lines in teeth, they’re not going anywhere. Cracks only have two physical options: stay the way they are or spread even more. Sort of like a run in an old pair of nylon stockings (does anyone remember those?!)

There is some good news. Even though there’s no way for cracks or lines on teeth to reverse themselves, there are things you can do to improve how they look or make them less noticeable. Such as whitening out the stains that have seeped down around them. 

You might find that whitening your teeth makes it look like the craze lines disappear altogether. But structurally, they’ll still be there. You might just have to dry the tooth off really well and look with a magnifying glass.  

How to Fix Craze Lines: Treatment Options

If you’re worried about visible lines on teeth when you smile, here’s some good news: you don’t have to do anything about them. Those tiny little cracks are more of a cosmetic issue than they are something requiring immediate dental treatment. If they don’t bother you, great.

As far as aesthetics go, you can treat craze lines in teeth by:

1. Covering them with dental veneers

When there are multiple lines in teeth, investing in porcelain veneers may be the best way to restore your smile to an attractive state.

2. Whitening your teeth

Whitening your teeth will help lift the stains inside of the cracks, making craze lines less visible when you’re smiling.

3. Having your dentist bond over them

Isolated lines in teeth can usually be covered up with tooth-colored composite. The entire procedure takes less than half an hour.

Since lines in teeth mean there are tiny surface cracks, you will want to be especially careful not to use your teeth to bite down into things. Like opening packages, biting your nails, or chewing on non-food items. If you do, you’re just going to apply more atypical force to your enamel and potentially cause the craze lines to get worse over time. The more they spread, the greater the risk there is of pieces of your teeth breaking off. Any time you grind teeth end-on-end repeatedly, it increases wear and tear.

How to Prevent White Lines in Teeth

Craze lines usually come from excessive pressure and biting force. The biggest piece of oral health advice to follow is not to use your tooth as tools. Teeth aren’t made to cut or tear things that aren’t food. When you do, you put excessive tooth-on-tooth pressure in areas that aren’t made to withstand it. Over time those repeated habits will wear down your teeth prematurely.

Similarly, ask your dentist to screen you for symptoms of bruxism or clenching/grinding. If you’re grinding your teeth out of stress or because of something like sleep apnea, it will speed up the wear and tear, and the development of craze lines on teeth. Usually, symptoms will include worn or flat enamel, TMJ pain, headaches, or prominent jaw muscles. You might need a night guard or bite splint. Wearing a night guard as directed will help with more than just preventing craze lines.

When to Talk to a Dentist

Not all lines in teeth are craze lines. You could have a significant fracture or cracked tooth that requires professional attention. If you see a line developing in your enamel or spreading deeper into your tooth, make sure to speak to your dentist about it. 

Since some lines on teeth are severe and others aren’t, your dentist will want to monitor craze lines over time. They might take an intraoral photo to keep in your digital records so that it can be referenced at each checkup. Or if the crack looks deep enough, they may need to take an X-ray or check for pressure sensitivity. Worst case scenario, deep cracks could allow bacteria to seep into the nerve of your tooth, resulting in an abscess. Early attention could mean the difference in needing a crown vs. a root canal. 

Overcoming the Appearance of Craze Lines

If you see visible lines on your teeth when you smile, don’t panic. It could just be something called “craze lines.” Usually, white lines on teeth will develop as we get older. Especially if we bite our nails, clench our teeth, etc. Addressing lines on teeth usually requires a cosmetic treatment like whitening or veneers. But if the crack is deeper than what’s on the surface it could mean more structural problems. Always see your dentist regularly to have lines on your teeth examined. With good home care and maintenance, you can keep your smile healthy and avoid painful dental emergencies.

 Whitney DiFoggio BS, RDH
Written by Whitney DiFoggio BS, RDH"Teeth Talk Girl," is a registered dental hygienist. She started her dental health journey on YouTube, educating the public through videos.
Dr. Matthew  Hannan DDS
Medical Reviewed byDr. Matthew Hannan DDSDr. Matthew Hannan is a board-certified dentist and graduate of UT Health San Antonio School of Dentistry.
Last updated onNovember 19, 2022Here is our process

Related Articles

Recommended reads