Dental Caries (Tooth Decay): Causes, Prevention, and Treatment
A plain-language overview of the most common chronic disease worldwide — how cavities form, who's at risk, and what actually prevents them.
Abstract
Dental caries — commonly known as tooth decay or cavities — is the most prevalent chronic disease worldwide. It is caused by acid-producing bacteria that damage tooth structure. This article reviews the biological mechanism of caries, established risk factors, and evidence-based prevention strategies, drawing on guidance from the U.S. National Institute of Dental and Craniofacial Research (NIDCR).
⚠️ For educational purposes only
This article reflects the research and opinions of the cited author(s). It is not personal dental advice — always consult a licensed dentist for diagnosis and treatment.
Key takeaways
- Dental caries — commonly known as tooth decay or cavities — is the most prevalent chronic disease worldwide.
- It is caused by acid-producing bacteria that damage tooth structure.
- This article reviews the biological mechanism of caries, established risk factors, and evidence-based prevention strategies, drawing on guidance from the U.S.
01What is dental caries?
Dental caries is the disease process that leads to cavities — permanently damaged areas in the hard surface of teeth that develop into tiny openings or holes. It is one of the world's most common health problems and affects people of every age.
Cavities are caused by a combination of factors: bacteria in the mouth, frequent snacking, sipping sugary drinks, and inadequate cleaning of teeth. If untreated, cavities get larger and affect deeper layers of the tooth, eventually leading to toothache, infection, and tooth loss.
02How cavities form
The inside of the mouth is full of bacteria. Some live in a sticky film called dental plaque that builds up on teeth. When you eat or drink anything containing sugar — including foods like bread, cereal, milk, juice, and candy — the bacteria in plaque use that sugar to produce acids that begin to eat away at the tooth's hard outer surface, the enamel.
Over time, this acid creates a hole in the enamel. Once the enamel is breached, the acid and bacteria can reach the softer dentin layer underneath, which is less resistant. Without treatment, the decay continues into the pulp — the tooth's nerve and blood-supply center — causing pain, sensitivity, and potentially infection.
03Who is at higher risk?
Everyone with teeth can develop cavities, but some factors increase risk:
04Symptoms
The signs and symptoms of cavities vary depending on their extent and location:
- Toothache, spontaneous pain, or pain with no apparent cause
- Tooth sensitivity
- Mild to sharp pain when eating or drinking something sweet, hot, or cold
- Visible holes or pits in your teeth
- Brown, black, or white staining on any surface of a tooth
- Pain when you bite down
You may not be aware of a cavity forming. That is why it is important to have regular dental checkups and cleanings, even when your mouth feels fine.
05Prevention
Good oral and dental hygiene can help you avoid cavities. The following are evidence-based prevention practices:
- 1Brush with fluoride toothpasteafter eating or drinking — ideally after every meal and at least before bed.
- 2Rinse your mouthif your dentist recommends a fluoride mouth rinse.
- 3Visit your dentist regularly— professional cleanings and oral exams can help prevent problems or spot them early.
- 4Consider dental sealants— a protective plastic coating applied to the chewing surface of back teeth. Sealants are recommended for all school-age children and remain effective for years.
- 5Drink some tap waterMost public water supplies have added fluoride, which can significantly reduce cavities.
- 6Avoid frequent snacking and sippingWhenever you eat or drink beverages other than water, you help mouth bacteria create acids that destroy tooth enamel.
- 7Eat tooth-healthy foodsSome foods and beverages are better for your teeth than others. Avoid foods that get stuck in grooves and pits.
- 8Consider fluoride treatmentsYour dentist may recommend periodic fluoride treatments, especially if you aren't getting enough fluoride.
- 9Ask about antibacterial treatmentsIf you're especially vulnerable to tooth decay — because of a medical condition, for example — your dentist may recommend special antibacterial mouth rinses.
06Treatment
If decay has already started, treatment depends on how severe it is:
07When to see a dentist
You may not be aware that a cavity is forming. That's why it's important to have regular dental checkups and cleanings, even when your mouth feels fine. However, if you experience a toothache or mouth pain, see your dentist as soon as possible.
This article is adapted from public-domain content published by the U.S. National Institute of Dental and Craniofacial Research (NIDCR) and MedlinePlus, services of the U.S. National Institutes of Health.
About the medical reviewer
U.S. National Institutes of Health
U.S. National Institute of Dental and Craniofacial Research (NIDCR) medically reviewed this article for clinical accuracy. They are not a SmileShop employee — their review is independent of any office listed on the site.
Attribution & License
- Original author
- U.S. National Institute of Dental and Craniofacial Research (NIDCR), U.S. National Institutes of Health
- Published in
- NIDCR Health Information · 2024-01-01
- License
- Public Domain
- How we got it
- Republished (Public Domain)
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