Tooth Decay and Cavities: Symptoms, Treatment, and Prevention

When you drink cold water or a hot cup of coffee, do your teeth feel sensitive? Or when you take a bite of food, do you notice a lingering toothache? If so, you may be experiencing tooth decay.

Tooth decay, also known as dental caries or cavities, develops when bacteria in the mouth create acids that damage tooth enamel. Diet, oral hygiene habits, saliva, and the overall oral environment all play a role in cavity formation.

Emerson Martins, D.D.S., M.S.c., Ph.D., a restorative dentistry expert with UAB Dentistry, explains how tooth decay occurs, how to recognize the warning signs, and what patients can do to prevent cavities before they become serious problems.

What causes tooth decay?

“Our mouth environment is always changing, and our saliva’s pH plays a big role in the dental caries,” Martins said. “If the pH decreases, the tooth will lose vital minerals and the decaying process begins.”

Acidic foods and beverages can lower the pH in the mouth, increasing the risk of tooth demineralization and cavity formation.

“For example, if you drink something that lowers your pH, you should rinse your mouth with water and use a dental product that contains fluoride to raise your pH and protect your teeth,” he said.

Martins recommends drinking tap water as a source of fluoride, which helps strengthen enamel and prevent tooth decay.

The stages of tooth decay

Tooth decay develops gradually and can become increasingly serious if left untreated.

Martins outlines six stages of tooth decay:

Stage 1: White spots
Stage 2: Enamel decay
Stage 3: Tissue (dentin) decay
Stage 4: Involving the innermost layer (pulp) of the tooth
Stage 5: Abscess formation
Stage 6: Tooth loss

Identifying decay early can help prevent progression to more extensive treatment needs.

Can cavities be reversed?

The good news is that early tooth decay can sometimes be reversed.

“If you notice signs of decay, your dentist can prescribe fluoride treatments like mouthwash to reverse early tooth decay,” Martins said. “You'll probably need a filling if you have a hole (cavity) in your tooth. If tooth decay has reached the soft tissue (pulp) in the middle of your tooth, you may need root canal treatment.”

While very early decay may be reversible, deeper cavities cannot be reversed once significant tooth structure has been lost. Professional treatment is needed to stop the damage and restore the tooth.

Signs and symptoms of a cavity

If tooth decay progresses, patients may experience:

• Toothache
• Tooth sensitivity
• Mild to sharp pain when eating or drinking something sweet, hot, or cold
• Visible holes in the teeth
• Brown, black, or white staining on the tooth surface
• Pain when biting down

Patients who notice these symptoms should schedule a dental evaluation as soon as possible.

How to prevent cavities

Preventing tooth decay is often simpler and less costly than treating it.

“You can prevent tooth decay by avoiding sugary drinks, brushing your teeth twice a day with fluoride toothpaste, and flossing once a day,” Martins said.

He also emphasizes the importance of managing carbohydrate intake and avoiding nighttime snacking.

“Avoiding dental caries is very simple with diet control. Managing when eating/drinking carbohydrates, brushing twice a day and flossing, and especially avoiding snacking before bed,” Martins said.

Modern approaches to cavity prevention

“At UAB Dentistry, we focus on gentle and effective treatments to keep your teeth healthy,” Martins said. “Instead of aggressive methods, we aim to prevent damage and, when necessary, make repairs rather than replacements.”

He notes that products designed to strengthen enamel and emerging technologies aimed at supporting tooth remineralization continue to expand treatment options for patients.

Why patient education matters

Martins believes prevention begins with education.

“Educating our population is the most important thing,” Martins said. “As dentists, we should invest more time in preventing these issues.”

He encourages patients to view cavity prevention as a partnership between dental professionals and individuals. By adopting healthy habits and seeking regular dental care, many cases of tooth decay can be avoided altogether.

More Patient Education

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