Dental Decay (Caries)

Dental caries, also known as tooth decay or cavity, is a disease wherein bacterial processes damage hard tooth structure (enamel, dentin and cementum). These tissues progressively break down, producing dental caries (cavities, holes in the teeth). Bacteria colonize on the tooth surface and in the presence of food debris, they multiply at a rapid pace. Decalcification of the tooth structure by acid producing bacteria (esp. Streptococcus mutans and Lactobacillus) initiates the development of decay. If left untreated, the disease can lead to pain, tooth loss, infection, and, in severe cases, death. Today, caries remains one of the most common diseases throughout the world. It is the  disease that: a) affects all ages and socio economic groups; b) is more prevalent than asthma; c) is second only to common cold; d) when left untreated, doesn't cure itself.

Dental caries is a multifactorial disease. It can develop only if four factors are present:

1. Bacteria
2. Host (Weak tooth surface)
3. Diet (Substrate for bacterial multiplication)
4. Time

The bacteria multiply at a rapid pace on the host surface (weak tooth surface) with the help of the substrate (food debris) and cause development of decay over a period of time.

Cavities commonly develop in three areas of the tooth surface:

1. In the grooves of the biting surface. Here, the cavity is surrounded on all sides by normal tooth structure and does not communicate with the adjacent tooth structure or gums. Fillings in such situations give excellent results... especially if the tooth decay has not gone close to the pulp chamber.

2. Between teeth - here, the cavities spread rapidly to the adjacent tooth structure, apart from creating a possibility for infection of the gum tissue in between the teeth.

3. Junction of the gums with tooth, especially on the labial / lingual side of the tooth.

In the case of cavities developing in the second and third areas
a) chances of spread of caries to adjacent teeth are high
b) chances of affliction of the gums and supporting structures of the teeth are high
c) pulp chamber of the involved teeth are close to the surface near the neck of the teeth and hence, a relatively small cavity is sufficient to cause pulpal involvement, necessitating root canal treatment.

Secondary caries
Caries developing under fillings is called secondary caries. This happens because of bacterial action on the weakened enamel beside the pre-existing decay. They are found most commonly in relation to amalgam fillings (commonly called silver fillings / metal fillings) as they do exert any preventive influence in the spread of caries. Recent filling materials such as glass-ionomer fillings and the nano composite fillings have protective effects and help prevent formation of secondary decay to a certain extent.

Untreated Dental Caries
Dental caries, if left untreated, spreads to the pulp chamber. Subsequently, the infection tracks down to the roots and the root tip. Very often, the abscess formed burrows through bone and forms a swelling in the gum area adjacent to the root tip.

Dental Caries / Decay Treatment & Prevention