Tooth decay can appear differently depending on the stage of severity. You may experience more symptoms, including pain and swollen lymph nodes, at later stages.

Tooth decay is damage that occurs to your teeth, which can potentially result in cavities, dental abscesses, or even tooth loss. It’s caused by the activity of certain species of bacteria that can live in dental plaque.

The bacteria in plaque can convert the sugars present in your food into acids. If plaque is allowed to build up over time, these acids can begin to damage your teeth.

This is why good oral hygiene is a vital part of preventing tooth decay.

Tooth decay occurs in several stages. Below, we’ll explore each of these stages, discuss how tooth decay is treated, and give you some tips on how to prevent it from happening.

Dental plaque is important to the tooth decay process. Plaque is a colorless, sticky film that covers the surfaces of your teeth. It’s made up of bacteria, food particles, and saliva.

If your teeth aren’t cleaned regularly, plaque can begin to build up. It can also harden over time, forming something called tartar. The presence of tartar can help to further protect bacteria, making them more difficult to remove.

Generally speaking, there are five stages of tooth decay. Let’s examine them in more detail below.

Stage 1: Initial demineralization

The outer layer of your teeth is composed of a type of tissue called enamel. Enamel is the hardest tissue in your body and is mostly made up of minerals.

However, as a tooth is exposed to acids produced by plaque bacteria, the enamel begins to lose these minerals.

When this occurs, you may see a white spot appear on one of your teeth. This area of mineral loss is an initial sign of tooth decay.

Stage 2: Enamel decay

If the process of tooth decay is allowed to continue, enamel will break down further. You may notice that a white spot on a tooth darkens to a brownish color.

As enamel is weakened, small holes in your teeth called cavities, or dental caries, can form. Cavities will need to be filled by your dentist.

Stage 3: Dentin decay

Dentin is the tissue that lies under the enamel. It’s softer than enamel, which makes it more sensitive to damage from acid. Because of this, tooth decay proceeds at a faster rate when it reaches the dentin.

Dentin also contains tubes that lead to the nerves of the tooth. Because of this, when dentin is affected by tooth decay, you may begin experiencing sensitivity. You may notice this particularly when having hot or cold foods or drinks.

Stage 4: Pulp damage

The pulp is the innermost layer of your tooth. It contains the nerves and blood vessels that help to keep the tooth healthy. The nerves present in the pulp also provide sensation to the tooth.

When damage to the pulp happens, it may become irritated and start to swell. Because the surrounding tissues in the tooth can’t expand to accommodate this swelling, pressure may be placed on the nerves. This can lead to pain.

Stage 5: Abscess

As tooth decay advances into the pulp, bacteria can invade and cause an infection. Increased inflammation in the tooth can lead to a pocket of pus forming at the bottom of your tooth, called an abscess.

Tooth abscesses can cause severe pain that may radiate into the jaw. Other symptoms that may be present include swelling of the gums, face or jaw, fever, and swollen lymph nodes in your neck.

A tooth abscess requires prompt treatment, as the infection can spread into the bones of your jaw as well as other areas of your head and neck. In some cases, treatment may involve removing the affected tooth.

Tooth decay in children

Children can also experience tooth decay. According to the Centers for Disease Control and Prevention (CDC), tooth decay is one of the most common chronic childhood conditions in the United States.

Children also may be more likely to experience tooth decay than adults. This is because the enamel of a child’s baby teeth is thinner and more sensitive than adult enamel.

Like it does in adults, tooth decay happens when bacteria break down sugars into acids, which damage tooth tissues.

Because of this, it’s important to make sure your child doesn’t consume too much sugary foods or drinks and that their teeth are brushed regularly.

Even though baby teeth are eventually lost, keeping them healthy is still vital. Not only do children need baby teeth for chewing and speaking, they also act as placeholders for adult teeth. If baby teeth are lost too early due to decay, adult teeth may not come in properly.

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The images below illustrate the different stages of tooth decay. You’ll see that as tooth decay progresses, more and more tissues of the tooth are affected.

The treatment that’s recommended for tooth decay can depend on its stage. Let’s take a look at the different treatment options based on the progression of tooth decay.

Initial demineralization

This earliest stage of tooth decay can actually be reversed before more permanent damage occurs. This can be achieved by treating the teeth with fluoride.

You can receive a fluoride treatment at your dentist’s office. It’s often applied to your teeth in the form of a gel or varnish. Fluoride works to strengthen enamel, making it more resistant to the acids produced by plaque bacteria.

Fluoride can also be found in some types of toothpastes and is often present in tap water. About 74 percent of Americans that get their tap water from a community water system receive fluorinated water.

Enamel decay

When tooth decay enters this stage, cavities are often present. Fillings are used to treat cavities.

When giving a filling, your dentist will first use a tool to clear away any areas of decay. They’ll then fill the hole with a material such as resin, ceramic, or dental amalgam. This material is typically the same color as your tooth.

Dentin decay

Because dentin is softer than the enamel, decay moves at a faster rate when it reaches this stage. If identified early, dentin decay may be treated with a filling. In more advanced cases, placement of a crown may be required.

A crown is a covering that covers the top portion of your tooth above the gums (also called the crown of the tooth). The decayed area is removed before the crown is placed. Some healthy tooth tissue may be removed as well to ensure that the crown fits well to your tooth.

Pulp damage

When tooth decay has reached the pulp, you’ll often need a root canal. In a root canal, the damaged pulp is removed. The tooth cavity is then cleaned and filled in. A crown is placed on the affected tooth.


If an abscess has formed in your tooth, your dentist will likely perform a root canal to remove the infection and seal the tooth. In severe cases, the affected tooth may need to be removed completely.

Antibiotics may also be prescribed to help treat an abscess. These are medications that kill bacteria.

Practicing good oral hygiene is an important part of preventing tooth decay. Below are some strategies you can implement to help avoid damage to your teeth from tooth decay.

  • See your dentist regularly: Your dentist can help to identify and treat tooth decay before it gets worse. Be sure to see your dentist regularly for routine teeth cleanings and oral exams.
  • Brush your teeth: It’s generally recommended that you brush your teeth at least twice per day and after meals. Try to use a fluorinated toothpaste.
  • Limit sweets: Try to avoid consuming foods or drinks with a high amount of sugar. Some examples include candies, cookies, and soft drinks.
  • Drink water from the tap: Most tap water contains fluoride, which can help keep your enamel strong and protect it from decay.
  • Avoid snacking: Aim to limit between-meal snacks, as this can give the bacteria in your mouth even more sugars to convert into acids.
  • Ask about sealants: Sealants are a thin coating of plastic applied to the tops of your back teeth (molars). Molars are important for chewing, but food particles can also get trapped in their grooves. A sealant covers the surface of the molar, preventing this from happening.

If tooth decay is in its early stages, you may not experience any symptoms. This is why regular visits to your dentist are important. Your dentist can help to identify and address the early stages of tooth decay before they worsen.

Make an appointment with your dentist if you experience tooth sensitivity, tooth pain, or swelling in or around your mouth. These may be signs of the later stages of tooth decay or another dental condition that needs attention.

Tooth decay is damage that affects your teeth due to the activities of bacteria present in dental plaque. These bacteria convert sugars from your food into acids, which can go on to damage teeth.

There are five stages of tooth decay. The earliest stage is often reversible, but later stages can cause permanent damage to an affected tooth.

The treatment for tooth decay depends on what stage it’s in. Some examples of potential treatments include fluoride treatments, fillings, and root canals.

There are steps that you can take to help prevent tooth decay. These include things like brushing your teeth at least twice a day, avoiding sweet foods, and making sure to visit your dentist regularly.