Dental Caries (Cavities)

Dental caries is the medical term for tooth decay. Bacteria in plaque feed on sugars and other fermentable carbohydrates and produce acid. Repeated acid attacks dissolve minerals from the enamel and the dentin beneath it. When the damage breaks through the surface, it forms a hole in the tooth, known as a cavity.

Why It Matters

Decay is one of the most common health conditions worldwide, and in its early stages it usually causes no pain, so it can progress unnoticed. Caught early, it can be stopped or even reversed without drilling. Left untreated, it spreads towards the pulp, causing pain, infection and eventually tooth loss.

Clinical Details

Stage 1: early demineralisation: A chalky white spot appears on the enamel. There is no hole yet, and this stage can be reversed with fluoride and better diet and cleaning.
Stage 2: enamel cavity: The surface breaks down and a small cavity forms. It may look brown or dark. It can no longer heal on its own.
Stage 3: dentin decay: Decay spreads faster in the softer dentin. Sensitivity to sweet, hot or cold is common.
Stage 4: pulp involvement: Bacteria reach the nerve, causing pulpitis and toothache.
Stage 5: infection: The pulp dies and an abscess can form at the root.
Diagnosis: Visual examination and bitewing X-rays, which show decay between the teeth that cannot be seen directly.
Treatment by stage: Fluoride varnish or high-fluoride toothpaste for early lesions; a filling once a cavity has formed; an inlay or onlay or a crown when much of the tooth is lost; root canal treatment when the pulp is affected; and extraction if the tooth cannot be saved.
Prevention: Brush twice a day with fluoride toothpaste and spit without rinsing, clean between the teeth daily, limit how often you have sugary food and drinks, and attend regular check-ups.

FAQ

What does a cavity look like?

Early decay looks like a dull white or chalky patch. As it progresses, it can turn light brown, dark brown or black, and a visible hole may form. Many cavities, especially between teeth, cannot be seen without an X-ray.

How do I know if I have a cavity?

Early decay usually has no symptoms. Later signs include sensitivity to sweet, hot or cold, pain when biting, a visible hole or dark spot, or food catching in one place. Regular check-ups are the most reliable way to find decay early.

Can a cavity heal on its own?

Only the earliest stage, before a hole forms, can be reversed with fluoride and good habits. Once enamel has broken down into a cavity, the lost structure cannot grow back and the tooth needs a filling or other restoration.