Dental Cavities

Dental Cavities, which is also known as Dental Caries or tooth decay, is a disease which damages the tooth structure, consisting of dentin, enamel and cementum, due to acid-producing bacteria. If the fermentable carbohydrates like fructose, sucrose and glucose are present in the teeth, the bacteria grows and breaks down the tissues in the tooth, leading to dental cavities or holes in the teeth.

The area affected by Dental Cavities may appear like a small chalky area but grow later into a largecavity. Dental cavities might affect the visible areas of teeth or even areas that are not directly visible. Tests like Radiography are conducted to detect dental cavities in areas which are less visible and to ascertain the extent of the damage of the tooth. Dental Cavities can lead to tooth loss, pain and infection, if not treated at the right time.

Classification of Dental Cavities:


Dental Cavities can be classified depending on its location, etiology, rate of progression and affected hard tissues.

  • Location: On the basis of its location, there are two types of dental cavities – Cavitiesfound in pits and fissures; and cavities found on smooth surfaces.
    1. Cavities found in Pit and Fissures: Pits are small depressions found at the cross-sections or ends of grooves while Fissures are located on palatal surfaces of front teeth or chewing surface of the rear teeth. Since there is deep infolding of enamel on all types of pits and fissures, maintaining oral hygiene is difficult, making them more prone to dental cavities. Also, dental cavities found in pits and fissures are difficult to detect.
    2. Cavities found on smooth surfaces: Cavities found on smooth surface are of three types – Proximal cavities, Root cavities and other smooth surface cavities. ProximalCavities, which are also known as interproximal cavities, are found between the teeth and are very difficult to detect while Root cavities are found on the teeth’s root surface and are caused due to exposure to gingival recession. The third type is found on any other smooth surface of the teeth and is the easiest to detect.
  • Etiology: In some cases, Dental cavities are described in a way which indicates its cause. ‘Baby Bottle Caries’, ‘Early Childhood Caries’ or ‘Baby Bottle Dental Cavities’ occur in children who fall asleep while drinking sweetened milk from the bottle or who frequently drink sweetened liquids during the day. ‘Rampant caries’ is another type of Dental cavities which is found in people who have poor oral hygiene, high sugar intake or those suffering from xerostomia.
  • Rate of Progression: There are three types of Dental Cavities depending on the rate of progression – Acute, Chronic and Recurrent. Acute Dental Cavities indicate that the disease is quickly developing while Chronic Cavities is described as a disease which has developed over a long period of time. Recurrent Cavities are cavities which affect a part time and again.
  • Affected Hard Tissues: Based on the hard tissues affected, Dental cavities can be described as cavities affecting enamel, dentin or cementum. Enamel cavities is the first stage of tooth decay and initially the cavities harm only the enamel while the term DentinalCavities is used when the cavities spread to deeper layer of dentin. Cementum cavitieshappen when the tissue covering the roots of the teeth are affected by the cavities.

Symptoms of Dental Cavities:

Initially the area affected by dental cavities may appear like a chalky spot which may turn brown and later lead to a hole in the teeth. Some of the symptoms of Dental cavities are pain in the tooth, visible holes in the teeth and foul breath. Exposure to too cold, hot or sweet foods and drinks may aggravate the pain.

Causes of Dental Cavities:

Dental Cavities may be formed due to four criteria – tooth surface, bacteria, fermentable carbohydrates and time.

  1. Tooth Surface: Individuals suffering from disorders or diseases affecting teeth like Amelogenesis imperfecta are more likely to be affected by dental cavities. Dentin and Cementum are more likely to be affected by cavities since the mineral content in them is quite low as compared to enamel.
  2. Bacteria: Though a large variety of bacteria is present in the mouth, there are only fewtypes of bacteria which can cause dental cavities. Lactobacillus acidophilus, Actinomyces viscosus, Nocardia spp and Streptococcus mutans are bacteria which cause dental cavities, especially root cavities. The Bacteria gathers around the gums and the teeth in the form of plaque which later develops into dental cavities.
  3. Fermentable Carbohydrates: The presence of fermentable carbohydrates like sucrose, fructose and glucose in the teeth lead to dental cavities. The bacteria present in the mouth turns the fermentable carbohydrates into acids like lactic acid. If the acid remains in contact with the tooth, the mineral content of the tooth may dissolve -- a process which is known as demineralization. If left unchecked, demineralization may lead to disintegration of the teeth and a hole in the teeth. However, the process can be neutralized with the help of mouthwash or saliva, which is known as remineralization.
  4. Time: If the teeth are frequently exposed to acidic environments, the chances of developing dental cavities are higher.

Diagnosis of Dental Cavities:

Most of the dentists visually examine the teeth to detect the dental cavities with the help of dental mirror and dental explorer. They also conduct Dental Radiographs or X-rays to detectcavities present in not-so-visible areas.

Treatment of Dental Cavities:

Though it is not possible to regenerate the damaged tooth structure, the treatment prevents further damage to the tooth. Dental Cavities can be treated by:

  1. Dental Restoration: In this treatment, the decayed tissue is removed after which materials like dental amalgam, porcelain, composite resin and gold are used to restore the missing tooth structure. If the damage to the teeth is too extensive that restorative material cannot be placed in the tooth, a crown, appearing like a cap, will be placed over the natural teeth.  
  2. Endodontic Therapy: This therapy is used in the cases where infection by decay-causing bacteria has destroyed the pulp in a tooth. In this treatment, the pulp and decayed portions of the tooth are removed which is then filled with gutta percha. A crown is then placed on the tooth.
  3. Extraction: The extraction of the decayed tooth is considered in cases, where tooth cannot be effectively restored due to the extensive damage caused by the decay process. This process may also be preferred by people who are unable to bear the expensive treatment for restoring the tooth.

Prevention of Dental Cavities:

  1. Dental cavities can be prevented by maintaining oral hygiene in the form of proper brushingof teeth and flossing every day. It is advisable to brush the teeth after every meal.
  2. It is advisable to go for regular dental check-ups and cleaning so that plaque can be removed from time to time, preventing its build-up.
  3. The frequency of sugar intake should be reduced since bacteria in the mouth turns carbohydrates like sucrose, fructose and glucose to acid, leading to demineralization process and eventually cavities.
  4. Infants or toddlers should not be given bottles of milk while they are sleeping.
  5. Consumption of calcium in the form of milk and vegetables is advisable to prevent dental cavities.
  6. Excessive consumption of junk food and cola drinks should be avoided.

Proper oral hygiene and limiting the consumption of sugar and junk food can help prevent dental cavities.