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Dealing with tooth decay is simple, right? You get a cavity and the dentist fixes it with a filling.

But today that's not the only way to handle tooth decay. Some dentists are using newer technologies to help detect decay as it begins and to treat it conservatively. The aim is to find out when the tooth begins to lose some of its minerals, before it develops a hole (cavity). At this early stage, decay often can be reversed.


The way a cavity forms has not changed. It starts with bacteria called Streptococcus mutans. They eat carbohydrates (found in sweets and many other foods) and produce acid. The acid attacks the hard outer surface of the tooth known as enamel. If the enamel surface breaks, then you have a cavity.

What has changed about the decay process is how long it takes. On average, a cavity does not break through the tooth surface for several years after decay begins, said David A. Albert, D.D.S., M.P.H., associate professor and director of community health at Columbia University College of Dental Medicine. Just a few decades ago, Dr. Albert said, a cavity could form in only months.

What has slowed down tooth decay? The short answer is "fluoride." Now almost all toothpastes contain this mineral, which strengthens teeth. It also is added to most U.S. water supplies. Because of fluoride, teeth are stronger than they used to be. They can fight off the loss of minerals in the early decay process.


Tooth decay often gives a warning before it causes an actual cavity. You or your dentist may see a white spot on the enamel, or your dentist may see a suspicious spot on your X-ray. New types of imaging and laser technologies also can help dentists to find early tooth decay. In some cases, it is a no-brainer to treat the decay with a filling. If you're in pain or have an obvious cavity, you need a filling. But "if there's no cavity and no pain, the tooth can fix itself," Dr. Albert said.

This works best if your overall risk of developing cavities is low. So, the next step is to assess your risk. Your dentist will ask questions and perhaps test the bacteria in your mouth. You probably are at low risk of cavities if you:

  • Have low levels of cavity-causing bacteria
  • Don't eat many sweet or starchy snacks
  • Have not had a cavity in the last year


Maintaining the health of teeth that have been demineralized from an acid attack is important. Good saliva flow is essential for preserving and remineralizing the tooth surface. Low levels of fluoride are very helpful in preserving the tooth surface and remineralizing early damage to the tooth. For children, we need to pay close attention to teeth when they first come into the mouth. They are more likely to be demineralized at that time because the tooth surface is not fully developed. For adults, demineralization of exposed tooth surfaces becomes an area for decay and break down. If you have orthodontic braces or clear aligners your teeth become more difficult to clean and they accumulate more plaque. The plaque often contains bacteria that can produce acids and demineralize your teeth. Teeth with crowns and bridges are also more susceptible to plaque accumulation and demineralization, particularly at the area where the crown margin comes in contact with the tooth at its base. Cleaning of that area

with good brushing and other aides such as floss is important to disrupt plaque and prevent demineralization.

The key message here is that the breakdown of the tooth surface is a process that is occurring all the time. Our mouths have bacteria that produce acid that damages the tooth surface. The damage can be prevented or reduced by frequent removal of dental plaque from all teeth, but especially from areas of teeth where food and plaque accumulate. Using home fluorides in combination with some dental office preventive treatments is the right approach to protecting your teeth, making them stronger, and keeping them that way.

To reduce your risk for a cavity, there are in-office preventive treatments that your dentist and dental hygienist can provide. Dental sealants can be placed on the surfaces of the teeth in deep pits where plaque and food accumulate. The dental sealants are plastic coatings that last for many years and prevent decay from developing.

If your risk is low, the dentist could paint fluoride varnish, silver diamine fluoride or calcium pastes on the problem tooth. These treatments often can stop or slow the decay process. They can help the tooth to repair itself. Your dentist also will work with you to improve your home brushing and flossing habits and possibly make changes in your diet. You may come back to the office more often during the next several months. The dentist will see if your tooth is improving and may treat it again. In many cases, the tooth will be repaired without a cavity ever forming. If you are at high risk for cavities, your dentist may add other treatments, such as mouth rinses to kill bacteria. Sometimes, if you are at high risk, the best treatment may also include placing a filling. People at high risk of cavities should visit the dentist more often than average.


Why not just remove the decay and fill the tooth for everyone? Dr. Albert noted that teeth without fillings are stronger. For example, there is always a chance that a filling will crack, break or fall out. The space between the filling and the tooth is also a hot spot for further decay.

Although newer technologies can help diagnose early decay, Dr. Albert recommended caution with treatment. "Some things look like cavities, but they're not. For example, a dark discoloration does not mean a cavity." So, if your risk of dental decay is low, Dr. Albert says it is better to "watch and wait" than "drill and fill."


Last updated June 30, 2021



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