Tooth Decay Explained: How Cavities Form, Early Signs, Prevention and Treatment

Tooth decay is the gradual breakdown of tooth enamel by acids that mouth bacteria produce when they feed on sugars and starches. Caught early, it can be halted or repaired with a small filling; left untreated, it can reach the nerve and may need root canal treatment.

Decay is one of the most common health conditions worldwide and can affect people of any age. The good news is that it is largely preventable.

How do cavities form?

A sticky film of bacteria called plaque builds up on teeth all the time. When we eat or drink sugar or refined carbohydrates, these bacteria produce acid that draws minerals out of the enamel. Saliva neutralises the acid and helps the enamel repair itself.

Problems arise when acid attacks happen so often that there is no time for repair. Frequent snacking, sipping sugary drinks throughout the day and inadequate cleaning tip the balance towards decay. A dry mouth, hard-to-clean areas between teeth and the margins of old fillings also raise the risk.

Early signs of tooth decay

Early decay usually causes no symptoms at all, which is why regular check-ups matter. As it progresses, you may notice:

• Chalky white, dull patches on the tooth surface
• Brown or black discolouration
• Brief sensitivity to sweet, cold or hot food and drink
• A hole you can see or feel with your tongue
• Food frequently getting trapped between teeth
• Pain when biting, or throbbing pain that starts on its own
• A bad taste or persistent bad breath

Treatment stages: from filling to root canal

Treatment depends on how far the decay has advanced. Very early lesions on the enamel surface, before a cavity forms, can often be stopped with fluoride and improved home care.

Once decay has broken through the enamel into the dentine, the decayed tissue is removed and the tooth is usually restored with a tooth-coloured composite filling. Where a large part of the tooth is lost, a stronger restoration such as an inlay, onlay or crown may be recommended.

If decay reaches the pulp, the nerve and blood supply inside the tooth, or the pulp becomes inflamed, root canal treatment is needed. The infected tissue is removed, the canals are cleaned, shaped and sealed, and the tooth is then usually protected with a filling or crown. If a tooth is too badly damaged to save, it may need to be removed, and options such as an implant or bridge can then be discussed.

Put simply, the earlier decay is treated, the smaller, quicker and more comfortable the treatment.

How to prevent tooth decay

Preventing decay is far easier than treating it, and small daily habits make a real difference.

• Brush twice a day for two minutes with a fluoride toothpaste
• Clean between your teeth daily with floss or interdental brushes
• Keep sugary foods and drinks to mealtimes and avoid constant grazing
• Choose water when you are thirsty
• Spit after brushing rather than rinsing, so the fluoride keeps working
• Attend check-ups at the interval your dentist recommends
• Ask about fissure sealants for children

When should you see a dentist?

If you notice sensitivity, discolouration or a hole in a tooth, do not wait. Pain that stops does not mean the decay has healed; sometimes it means the nerve has been damaged. If you have facial swelling, a fever or severe pain, contact a dentist promptly.

You can book an examination with Dr. Merve Hakan to have your teeth assessed and, if treatment is needed, plan the least invasive option together.