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Everything you need to know about cavities

What is a cavity? It is a dental disease caused primarily by inadequate hygiene. Without regular cleaning, pathogenic bacteria survive on the teeth, producing acids that gradually erode the tooth enamel.

Continue reading if you want to avoid a black spot on your tooth.

Symptoms of cavities

Mostly, the symptoms of cavities are easy to detect. Pay attention in case of persistent pain or increased sensitivity of teeth. One of the symptoms of weakened tooth enamel may also be yellow enamel (this is not a guaranteed symptom). Naturally, there can sometimes be hidden cavities that only a dentist can detect.

Most common symptoms of cavities:

  • Persistent pain
  • Increased sensitivity
  • Visible pits in the teeth
  • Black enamel
  • Dark spots on jaw X-rays

What kind of pain does a cavity cause?

Minor cavities rarely announce themselves with pain. It hurts only when the cavity significantly damages the tooth enamel.

The pain is signaled by dental nerves, which are not sufficiently protected by the damaged enamel.

Why are teeth with cavities more sensitive?

Even a small cavity weakens the enamel. The nerves in the teeth are then more exposed and sensitive to external stimuli.

How deep can pits in teeth be?

Cavities appear in various forms and intensities. Often, you may discover a cavity as a black dot. More intense cavities are larger pits of brown or black color. Large, often difficult to save, decayed teeth have noticeable holes.

Is black enamel always a cavity?

Black enamel is likely caused by a cavity, but it should be noted that yellow discoloration is not always a sign of a cavity. Pigmentation can also be acquired through genetic predispositions, age, diet, smoking, or medications. Conversely, white spots on the teeth may occur due to excessive use of fluorides (known as fluorosis).

Causes and development of cavities

Cavities in teeth occur for several reasons. The most common is poor oral hygiene. So, for the most part, people are responsible for their own cavities. Do not underestimate the importance of oral hygiene.

Diagnosis of cavities

The start of a cavity in a tooth, and especially a large cavity, should prompt an urgent visit to the dentist.

How cavities are diagnosed at the dentist:

  • Using a probe and mirror
  • Caries detector
  • Fluorescence
  • X-ray image

Dental probe and mirror

The dental probe and mirror are the most common tools for diagnosing cavities. The doctor uses these dental instruments to look for soft or discolored spots on the teeth. The method is not as precise as an operating microscope, but experienced dentists usually detect cavities.

Caries detector

The Caries Detector reveals demineralized collagen fibers in cavities using a special dye. This method requires the experienced eye of a dentist, as it can sometimes stain healthy dentin as well.


Fluorescence is a more reliable method for detecting cavities than the Caries Detector, but not all dentists have this technology, as it has higher acquisition costs.

Dental cavities on X-ray

Dental cavities are not always visible to the human eye. To detect primarily interdental cavities and cavities under dental fillings, an X-ray is necessary.

Dentists typically make it a practice to use an X-ray once in a while to detect signs of dental cavities. The process is as follows: The dentist will have you bite down and take an X-ray of the jaw (called a bite-wing). The image is then immediately checked and evaluated.

What does a cavity look like on an X-ray? On the image, the dentist will look for dark spots caused by the reduced amount of minerals in the cavity.

Intensity of cavities

Upon detecting a cavity in the mouth, the dentist will assess how to proceed in the fight against decayed teeth.

Levels of cavity intensity:

  1. Acute cavity
  2. Chronic cavity
  3. Arrested cavity

Immediate action is required when the decayed material is light yellow and the cavity is spreading rapidly. If the decay progresses slowly and the carious lesion (spots on the enamel surface) is darkly colored, it is considered a chronic cavity. An arrested cavity is characterized by a darkly pigmented, completely hard base.

Types of cavities (+ images)

A tooth is composed of several parts that are susceptible to cavities. Cavities at the gumline, cavities on the side of the tooth, and black tooth enamel can appear on teeth anywhere.

The types of cavities are:

  • Enamel cavity
  • Dentin cavity (dental tissue)
  • Cementum cavity

Interdental cavities are often overlooked because they are not immediately visible until they become significantly developed. Fortunately, a dentist can detect them during regular check-ups. Moreover, careful cleaning with an interdental brush makes it more likely that they won't develop at all.

Enamel cavity

Enamel cavity begins with the action of organic acids that demineralize the surface of the teeth. Due to demineralization, a carious lesion forms in the shape of a chalky white spot (known as a white spot). Subsequently, the weakened enamel is more susceptible to the full onset of a cavity.

Cavity of the dentin (dentine)

When demineralization reaches excessive levels, the enamel is weakened, and microorganisms that produce organic acids penetrate to the dentine. A dentin cavity needs to be addressed with a filling to prevent the tooth from dying.

Dentin cavities are characterized by a conical shape that appears as black plaque on the teeth.

Cementum cavities

Cementum cavities most often occur as a result of aging (known as atrophic changes) in people over 60 years old. Over the years, or due to periodontitis, the gums recede and cavities form around the exposed root.

Cavities vs. enamel erosion

There is often confusion between tooth erosion and tooth decay. Tooth erosion is a phenomenon where teeth lose enamel and become weakened. Subsequently, weakened teeth are more susceptible to cavities.

Enamel erosion is increasingly common due to changes in societal diets towards high consumption of highly acidic sodas. Frequent causes of erosion also include unprofessional and homemade teeth whitening, or regular use of highly abrasive whitening toothpastes.

Cavity prevention

How to check for cavities? If you regularly visit the dentist and maintain dental hygiene, you won't need to check your teeth yourself, as professionals can detect the onset of cavities. They can also spot decay between teeth and other dental problems.

How to prevent cavities:

  • Maintain oral hygiene
  • Avoid acidic drinks in your diet
  • Ensure sufficient intake of minerals
  • Visit the dentist and dental hygienist
  • Whiten teeth cautiously (ideally not at all)

Proper oral hygiene against cavities

Generally, it's necessary to adhere to a cleaning routine. Use a soft brush, respect the cleaning technique as instructed by your dental hygienist, clean your tongue as well, and don't forget to use interdental cleaning and mouthwash. It doesn’t matter whether you use a toothpaste specifically for cavities; almost all toothpastes contain re-mineralizing and antibacterial ingredients to some extent.

Diet without acidic drinks

A proper diet prevents bad breath and also serves as a prevention against cavities. Generally, it is good to avoid foods and drinks with high acidity.

If you indulge in a sweet soda, wait 30-60 minutes before brushing your teeth. Teeth are more sensitive after consuming very acidic foods. Immediate brushing could mechanically irritate the teeth at a time when they are more susceptible to damage.

Which minerals protect tooth enamel

Tooth enamel is, after all, similar to bones. It’s not surprising that calcium helps the enamel. In combination with magnesium, the enamel strengthens and becomes more resistant to acids. Doctors recommend maximizing the effect by enriching the mix with zinc.

Vitamins also help to enhance the mix for strong tooth enamel. Vitamin K2 and D3 support the absorption of calcium, making it easier for calcium to reach where it's needed.

Suitable mix of minerals and vitamins for strong enamel:

  • Calcium
  • Magnesium
  • Zinc
  • Vitamins D3 and K2

When and where to visit a dentist

Teeth with cavities should be unfamiliar to you if you regularly visit professionals.

A child's initial dental visit should occur when the first tooth emerges, and ideally continue twice a year for life. It's also important to visit a dental hygienist twice a year, starting when a child gets their first set of 20 teeth.

Safe teeth whitening

Beautifully white teeth enhance attractiveness, but teeth whitening can be dangerous for tooth enamel. Whitening itself is not a cause of cavities, but subsequently weakened enamel is more susceptible to cavities.

If you still want to undergo the procedure despite the risk of damaging your teeth, avoid unprofessional home whitening.

Before in-office whitening, visit a dental hygienist to ensure there is no tartar on your teeth. Also, make sure that your gums and tooth necks are isolated from the whitening gel containing hydrogen peroxide.

After whitening, you will likely experience tooth pain and sensitivity because the teeth will be very dehydrated. This should subside within 24 hours.

Treatment of cavities

The more a cavity is neglected, the more drastic the subsequent treatment becomes. Minor cavities, gum inflammation, or disinfection of root canals can be painlessly addressed with ozone therapy. Larger cavities will likely need to be drilled and filled. If a tooth with a cavity is in its final stage, it must be completely removed.

How cavity treatment is carried out:

  • Using ozone therapy
  • Drilling and filling the tooth
  • Removing the tooth, if necessary

There is no need to fear these procedures. Ozone therapy is a modern method that is completely painless, and local anesthesia precedes other procedures.

Ozone therapy

Ozone therapy is a treatment using a special device that generates ozone and applies it to the damaged area of the tooth. According to clinical studies, ozone application can destroy 999,999 out of a million bacteria. Ozone from these devices penetrates up to 3 millimeters deep into the tooth tissue. Ozone therapy is a modern and painless method for treating cavities and cavity precursors.

Drilling and fillings

The least favorite treatment for cavities is drilling, likely one of the dental procedures most feared by people.

First, it’s important to realize that with proper prevention, cavities need not develop at all. However, if the dentist must proceed with drilling and grinding the tooth, the area is locally numbed. You won’t feel anything. After the cavity is removed, the tooth is filled with a special material (filling).

Types of dental fillings:

  • Amalgam (silver-black)
  • Glass ionomer (white, less aesthetic)
  • Composite (white, highly aesthetic)

Tooth extraction

Teeth with cavities that have been neglected for a long time can develop serious inflammation. At this point, it is necessary to remove the tooth to prevent more serious problems (e.g., inflammation of the dental pulp or diseases of the root canals).

Tooth extraction is the most drastic option in combating cavities. Dentists always fight to save a tooth. The option of extraction is chosen only when there are no other alternatives.


Always discuss cavity with your dentist.


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