Cavity vs. Stain: How To Tell And What To Do

Cavities and stains have many similarities. Find out how to tell them apart and which steps you should take if you have either one.

December 29, 2021
Cavity vs. Stain: How To Tell And What To Do

Although dental cavities and dental stains look similar to each other, the reasons you get them and the ways to treat them are quite different. 


To help you tell them apart and to seek the appropriate treatment, here’s a guide from Flossy on everything you need to know about cavities and stains. 

What Is a Cavity?

A cavity—otherwise referred to as tooth decay—is what happens when your tooth enamel begins to experience damage. Essentially, it’s a small opening in your tooth. In the beginning, it can look like a tiny white spot. However, it can progress into a larger gray, brown, or black opening over time. 


Cavities form thanks to plaque—the sticky film that forms on top of your teeth and gums. The bacteria in the plaque feed on the sugar in your food and release acids as a result, which eats away at the protective coating of your teeth. 


If the damage isn’t addressed immediately, it can eventually reach your tooth's middle and inner parts. Because your tooth’s nerve endings are located on the inside of the tooth, a cavity can cause you to experience sensitivity and pain. Down the line, tooth decay may even require a root canal. 

What Causes a Cavity?

For the most part, tooth decay is caused by excessive sugar consumption and poor oral hygiene. 


The bacteria found in plaque feed on the sugar in sweet and starchy foods, which allows it to multiply. In addition, as the bacteria eat the sugar, they release an acid that erodes tooth enamel. This erosion marks the beginning of tooth decay, which can progress into the middle and inner layers of the tooth if left untreated. 


One of the best ways to prevent tooth decay is to brush and floss regularly. Brushing clears away plaque from your teeth and gums, while flossing gets plaque that’s hidden in-between the teeth. However, many U.S. adults don’t follow the recommendation to brush and floss twice daily, which can lead to plaque build-up, new cavities, or worsening of pre-existing tooth decay. 

To a small extent, your genetics play a role in how likely you are to get cavities. For instance, your genes determine how your teeth develop and influence how strong your enamel is in fighting bacteria. However, tooth decay can be avoided even in this case by following a consistent oral hygiene routine. 

What Is a Stain?

Unlike cavities, stains usually aren’t an indicator of tooth decay and—in many cases—are nothing to be concerned about. Simply put, dental stains are the discoloration of your teeth. You may notice an all-over change in color or a small stain on one part of your tooth. 


Dental stains can be classified into roughly two types: intrinsic or extrinsic. Extrinsic stains are discoloration in the outermost layer of the tooth—the enamel. On the other hand, intrinsic stains happen to the middle layer of the tooth—the dentin. In general, the latter is more permanent and less likely to respond to at-home remedies. 

What Causes a Stain?

Extrinsic staining occurs due to some staining agent that you’ve come in contact with. This includes common foods and drinks such as coffee, tea, red wine, and even certain berries. In addition, smoking can stain your teeth, thanks to the tobacco, tar, and nicotine that most cigarettes contain. 


Intrinsic staining occurs in the middle layer of your tooth—called dentin. This type of discoloration is more deep-set and is less impacted by your lifestyle choices. This type of discoloration can be caused by demineralization, a process in which your teeth lose vital minerals, or dental fluorosis, which occurs due to excess fluoride consumption. In addition, the use of tetracycline antibiotics during pregnancy has been linked to teeth discoloration. 


Lastly, age might have something to do with teeth discoloration, as well. As your enamel wears away, the middle layer of your teeth—the dentin—will be more visible. Since dentin is naturally yellow, this process may give you the appearance of teeth that look less white over time. 

Cavity vs. Stain: What’s the Difference?

Because they both manifest as a change in the color of your teeth, it might be easy to confuse cavities and stains. However, there are a few sure ways to distinguish between the two.


First of all, you might want to consider how widespread the “stain” appears. If an entire tooth (or multiple teeth) appears discolored, then it’s likely a stain. However, if you notice a small spot of discoloration on your tooth, then it’s very likely a cavity.


In addition, cavities appear dark brown or black. While this is also the case for some stains (such as those caused by tobacco), most dental stains are much lighter in color. 


Finally, a dark spot isn’t the only sign of a cavity. Because a cavity is essentially damage to the tooth, you’ll experience a host of other issues along with it. This includes increased sensitivity to hot or cold foods and beverages, tooth pain that can radiate up to your jaw, and a visible hole in your tooth. 

What Should I Do If I Notice a Cavity or Stain?

Once you’ve identified whether you’re dealing with a cavity or a stain, there are some things you can do to address the problem most effectively. 

Dental Cavities

Unfortunately, there’s no at-home treatment for cavities. While there is plenty you can do to prevent a cavity from forming in the first place, this isn’t exactly helpful when a cavity has already begun to develop. Indeed, the only thing you can do is to schedule an appointment with your dentist as soon as possible so you can get it treated. 


Based on the size of the cavity, your doctor might recommend several treatments. Most commonly, this includes getting a simple filling, in which the decay will be removed, and your tooth will be filled in with a resin that’s the color of your tooth. 


Your dentist might also recommend a crown for more serious cavities, which will fit over the entire tooth. And if the cavity has spread from the surface to the inner layers of the tooth, then your dentist might recommend doing a root canal. 


Of course, more cavities can form in the future. For this reason, it might be helpful to follow these tips: 


  • Keep a consistent routine: Make sure to brush and floss at least twice per day to remove plaque from your teeth and gums. 


  • See your dentist regularly: Schedule dental cleanings at least once every six months to remove hard-to-reach plaque and tartar buildup. 


  • Consider using fluoride: Use toothpaste or mouthwash containing fluoride to strengthen the enamel on your teeth. 


  • Limit sugar: Limit consumption of sugary foods and drinks to keep plaque bacteria from feeding on it. 


  • Ask your dentist about sealants: Sealant is a protective coating that’s applied to the teeth. It can be very effective in protecting the enamel of your teeth from food and plaque. 

Dental Stains

If the stains on your teeth result from lifestyle choices (such as smoking), then the stains are surface-level and can be easily removed at home. If you’re noticing mild discoloration, then you can try at-home whitening products, such as toothpaste, gel, or strips. If they don’t do the job, then you can see your dentist for professional whitening. 


However, if the staining is situated in the middle layer of your teeth, whitening products won’t penetrate deep enough to make a difference. In this case, you will need to see your dentist for other options. 


One option your dentist might recommend is dental bonding, which involves placing a resin on the top of your teeth. This resin will be lighter in color than your teeth, giving them a brand-new appearance. A similar option might be to get veneers, which involves placing a porcelain “shell” on top of your teeth—an instant improvement in both color and shape. 


Because stains can always get worse, it’s important to practice prevention. Here are some of the things you can do to keep dental stains from progressing:


  • Use fluoride: Using dental products with fluoride will go a long way in strengthening the enamel of your teeth, which will protect them from staining. 


  • Drink through a straw: Drinking wine, coffee, and tea through a straw will limit the contact your teeth have with these staining beverages. 


  • Rinse immediately: If drinking with a straw isn’t for you, then you can simply try rinsing immediately after consuming staining beverages. 


  • Quit smoking: Smoking (or using tobacco products in any way) is one of the surest ways to stain your teeth. Quitting smoking will make an immediate improvement in the appearance of your teeth. 

For a Brilliant Smile

Although cavities and stains may look similar, there are a few main differences between the two. A cavity is a form of tooth decay, which should be treated immediately by a professional dentist. Tooth discoloration, on the other hand, is relatively harmless and can be easily fixed with whitening products. 


If you’re experiencing any of these common dental issues, then Flossy can help you find your next dental professional—for your most brilliant smile yet. 



Our Sources:

Positive Association  Between Sugar Consumption and Dental Decay Prevalence Independent of Oral Hygiene in Preschool Children | NCBI

Demineralization–Remineralization Dynamics in Teeth and Bone | NCBI 

Interventions in Management of Dental Fluorosis | NCBI

Preventing Decay with Fluoride | California Dental Association