Types of Caries and their Causative Organisms

Dental Caries as described earlier is an irreversible microbial disease of the calcified tissues of the teeth, characterized by de-mineralization of the inorganic portion and destruction of the organic substance of the tooth. Caries when translated in Latin means ‘rot’ or ‘decay’ and Dental Caries means rotten or decayed teeth. Dental Caries was not seen in Prehistoric man particularly Pre Neolithic periods (12,000 BC) in this era the dolicocephalic skulls did not exhibit dental caries.

Dental caries were first seen in skulls starting from Neolithic periods (12,000 to 3,000 BC) from brachycephaic man. Dental caries is a microbial multifactorial disease of calcified tissue of teeth, characterized by demineralization of the inorganic portion and destruction of organic content.

As you have seen in the Post about Dental Caries there are 4 Types of Caries in particular based on the location where they are seen on the tooth and the causative organisms for each type also differ which is given below categorized under each type.

Types of Bacteria causing Dental Caries:

Bacteria or Microorganisms produce acid rapidly from fermentable carbohydrates which is called acidogenic. These aciduric conditions help the microorganisms to thrive and multiply rapidly. The bacteria produce extracellular and intracellular polysaccharides which lead to formation of plaque matrix, intracellular polysaccharides can be used for energy production and converted to acid when sugars are not available.

1) Pit & fissure Caries

• S mutans
• S sanguis
• Other streptococci
• Lactobacillus sp
• Actinomyces sp

2) Smooth surface Caries

• S mutans
• S salivarius

3) Root surface

• A viscosus
• A naeslundi
• Othr filamentous rods
• S mutans
• S sanguis
• S salivarius

4) Deep dentinal caries

• Lactobacillus sp
• A naeslundi
• A viscosus
• Other filamentous rods
• S mutans

Carries Susceptibility based on type of Tooth:

• Upper and lower first molars: 95%
• Upper and lower second molars: 75%
• Upper second bicuspid or premolar: 45%
• Upper First bicuspid or premolar: 35%
• Lower second Bicuspid or premolar: 35%
• Upper central and lateral incisor: 30%
• Upper cuspid or canine and lower first bicuspid: 10%
• Lower central and lateral incisor: 3%
• Lower cuspids: 3%

Most of these bacteria are present in the oral cavity even when there is no dental caries, in case of improper brushing and poor oral hygiene maintenance, these bacteria settle down in the damaged surface of the tooth. The bacteria causing different types of caries differs as the location is different and the conditions as well.