Cavities commonly called as “Tooth decay is damage to the outer protective layer of the tooth i.e. enamel.

It is the most prevalent chronic disease in both children and adults. Tooth Decay (Dental caries) happens when bacteria in mouth make acid that attacks the enamel. It can lead to cavities, which are holes in the teeth. If it is not treated well in time, it can cause pain, infection, and even tooth loss.

In most developing low-income countries, the prevalence rate of dental caries is high and more than 90% of caries is untreated. An estimated 5 billion people worldwide suffer from dental caries.


Tooth surfaces are rough, uneven and a favourite place for cavity-causing bacteria to hide and where leftover food also gets accumulated. These bacteria combine with food and constantly form a soft, sticky film called plaque. When we eat or drink foods containing sugars, the bacteria in plaque produce acid that attacks the tooth enamel. Due to stickiness of the plaque this acid remains in contact with our teeth and over time damages tooth enamel and causes cavities.

The development of caries requires sugars and bacteria to be present. It is influenced by the susceptibility of the tooth, the bacterial profile, quantity and quality of the saliva, low levels of fluoride, and the time for which dietary carbohydrates are available in the oral cavity for bacterial fermentation (i.e. the frequency of sugar intake).

Salvia and fluorides, helps the enamel to repair itself by replacing the minerals. Teeth go through this natural process of losing minerals and regaining minerals all day long. But if we don't take care of our teeth and/or eat and drink lot of sugary things, enamel will keep losing minerals leading to tooth decay.


In the beginning, there may not be any symptom at all. As the decay extends, it may cause signs and symptoms:

  • White or brown spots on tooth appear where minerals have been lost as an early sign of tooth decay.
  • Sensitivity to hot, cold or even sweet foods
  • Difficulty in chewing food
  • Toothache
  • Visible holes or pits in teeth
  • Food trapping in between teeth
  • It can also harm the nerves in the teeth and the roots.


Main causes and risk factors for tooth decay are:

1. Not taking care of your teeth like-

  • not brushing twice daily
  • not rinsing mouth after meals
  • having too much sugary or starchy foods and drinks.

2. People at higher risk of tooth decay are those who:

  • drink from bottles (babies and toddlers), especially if they are given feeders with sugar mixed milk or juices at bedtime. This exposes their teeth to sugars for long periods of time. Their gum pads should be cleaned with a neat cotton cloth after feeding.
  • Don't get enough fluorides.
  • Have reduced saliva because of some drugs, certain diseases, or some cancer treatment.

3. Back teeth (molars and premolars) have uneven surface that can trap food particles and are more prone to decay. 

4. Sticky foods such as toffees, chocolates, ice cream, honey, sugar, soda, dried fruit, cake, cookies, hard candy and mints, dry cereal, and chips increase chances of tooth decay.

5. Frequent snacking and sipping sugary drinks provide mouth bacteria more carbohydrates to produce acid that attacks teeth and causes decay.

  • Good oral hygiene is the first step to prevent tooth decay.
  • Brush with fluoride toothpaste twice daily.
  • Clean between your teeth using floss or an interdental cleaner.
  • Limit sugary snacks between meals and also limit added sugars and high-acid foods.
  • Avoid foods that get stuck in grooves and pits of teeth or brush /rinse soon after eating them.
  • Rinse your mouth thoroughly after meals.
  • Chew sugar-free gum with xylitol, which can promote salivary flow.
  • Whenever possible, drink some tap water as public water supplies have added fluoride, which help in reducing tooth decay significantly.
  • The Center for Disease Control and Prevention (CDC) recommends sealants for all school-age children. Sealants protect tooth by sealing off the uneven tooth surface, that tend to collect food.
  • According to the CDC, "school-age children without sealants have almost three times more cavities than children with sealants."
  • Make regular visits to dentist to identify tooth decay.


Treatment choice depends on the intensity of tooth decay.

  • Early stages of tooth decay can be managed by fluoride treatment.
  • Fluoride toothpaste strengthen the teeth and offer the best protection from tooth decay. Especially low dose toothpaste with 0.05% fluoride [often listed on the package as “500 ppm” (parts per million)] in it, is available for younger children.
  • Toothpaste with 0.1% fluoride in it (more than 1000 ppm) is only recommended usually when the child is about six years old.
  • If you have a cavity in your tooth, your dentist will clean the decayed tooth and then fill the tooth with a filling material.
  • If the damage/ infection of tooth has spread to the pulp (inside the tooth), then a root canal is required.
  •  In severe cases, when the damage to the tooth cannot be fixed, dentist may pull (extract) the tooth. Replacement of missing tooth is suggested after wound healing.


  • It is recommended to visit your dentist every six months.
  • People who have healthy teeth and gums are advised to visit once a year.
  • For people who have dental problems, more regular check-ups are recommended.




  • PUBLISHED DATE : Apr 16, 2019
  • CREATED / VALIDATED BY : Dr Rida Ziaul
  • LAST UPDATED ON : Apr 16, 2019


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