Dental caries commonly occur on chewing surface or the inter-dental surfaces in posterior teeth. The chewing surfaces of back teeth are wide with pits and fissures for easy retention of food debris and microorganisms.

Nursing Bottle Caries:

In case of children when bottle-feeding is done for prolonged periods and at night, a special pattern of dental caries occurs. In this disease there is fast destruction of upper front and lower back teeth sparing lower front teeth because they are covered with tongue during feeding. This particular pattern of dental decay is called as Nursing Bottle Caries. This condition requires early and proper treatment otherwise it may lead to many other problems and may cause abscess or swelling in the oro-facial region.

If dental caries is left unattended, it may lead to dental abscess. This abscess appears as swelling on gum or sometimes it may spread to the face and neck region. This spread may result in fever, excessive swelling or sometimes in death. Treatment of dental caries in milk teeth is more important because if it is not treated in time, these teeth may fall before time leading to complication in eruption of permanent teeth.

The Causation of dental caries

Now, the question arises that how does dental caries occur. The causation of this disease involves complex interaction between the bacteria present in mouth, food remnants especially carbohydrates and the tooth surface. Let us discuss each in details.

Bacteria

Bacteria are very small organisms not visible by naked eye. Every person has bacteria in his/her mouth. These bacteria live in a slimy transparent layer on tooth. This slimy layer is called as plaque. This is mainly composed of bacteria, salivary proteins, few cells and some bacterial products. The plaque is normally not visible on tooth surface. This can be easily seen by rinsing with a special dye (mercurochrome/ erythrocine) called as disclosing agent. This disclosing agent will colour the plaque.

How do bacteria stick to the tooth surface?

The bacteria stick to tooth surface with the help of end products of carbohydrate metabolism and salivary proteins. When the food remnants especially carbohydrates come in contact with the bacteria present in plaque, fermentation process starts. The bacteria produces acid a result of this fermentation, which in turn causes dissolution of tooth surface leading to dental caries.

How does the acid dissolve the tooth?

The initial attack of bacterial acid is on enamel and the dissolution starts. During this time this may appear as brownish or black discoloration of tooth. On progression, this converts into a cavity or a hole in the tooth. At this time the usual complain is that the food gets impacted between the teeth. Further progression of this lesion leads to involvement of dentin. During this time normally the patients complain of sensitivity to heat and cold or sweet and sour things. If this is not treated even now it may lead to involvement of pulp and subsequent abscess formation.

What does your dentist do when you have dental caries?

Dentist can fill the cavity till the time the caries has not involved the pulp. The filling is usually done with specially prepared silver amalgam or some other tooth coloured material. Once the carious process involves pulp the tooth needs root canal treatment. During this treatment, the dentist removes infected/decayed pulp from the root canals of the tooth and fills the canals with some inert material and finally the tooth can be restored with filling or a cap as per the requirement. The placement of cap or crown is considered as necessary for a root canal treated tooth.

What will happen if the dental caries will not be treated?

The tooth decay will first involve enamel and then dentin, at this time you can have some sensitivity of the tooth on eating hot and cold things. After this the bacteria causing the decay will reach to the pulp and you can have pain in the tooth due to that. The bacteria may further invade the underlying bone, gums and other adjoining tissues if the treatment is not done in time leading to swelling pus discharge, fever etc.