Dental caries or tooth decay and periodontal disease are probably the most common chronic diseases in the world.
Although caries has affected humans since prehistoric times, the prevalence of this disease has greatly increased in modern times due to dietary changes.
However, evidence now indicates that this trend has begun to decline in many countries in the late 1970 and early 1980 and the decline was most notable in certain segments.
Dental Caries is an infectious microbiological disease of the teeth that results in localised dissolution and destruction of calcified tissues of the teeth.
It is very important to understand that cavitations in teeth are the signs of bacterial infection in clinical practice and not the disease itself.
It is possible to lose sight of this fact and focus entirely on the restorative treatment of the carious legions thereby, failing to treat the underlying cause of the disease.
The evidence for the role of bacteria in the genesis of caries.
Overwhelming animals and human models have been used in an extensive series of studies leading to the following conclusions:
- Teeth free from bacterial infection either in germ free animals or un-erupted teeth in humans do not develop caries.
- Oral bacteria can demineralised the tooth in in-vitro and produce lesions similar to Naturally occurring caries.
- Specific bacteria can be isolated and identified from plaque over various carious lesions.
Although the role of bacterial activity in the genesis of carious lesion is well defined, establishing a cause and effect relationship between individual organism in the oral flora and caries has not been completely successful.
Oral bacteria do not occur as solitary colonies but as members of the complex community of many species contained as a massive tightly packed cells held together by the sticky matrix of polymer glucose known as "Dextran".
Sturdvant's Art & Science of Operative Dentistry, 4th Edition.