Tooth Decay – Origin and Consequences

According to the World Health Organization (WHO), the tooth decay is one of the most common chronic diseases in humans. It can reach to all teeth as the permanent disease. The decay is a disease generated by the interaction of four factors and develops in four stages.

Factors for development of caries: schema Keyes

The development of a carious lesion is due to the coexistence of four factors: plaque, land, food and time.

Bacterial plaque

In the oral cavity of a human being, more than 60 different species of bacteria live who participates in the formation of bacterial plaque (see scale and scaling). Some of these bacteria like streptococcus and / or lactobacillus produce acids that can attack the mineralized tissues of the tooth and cause tooth decay as well. The risk of developing cavities will be even greater than the number of bacteria present in the mouth is important.


Some people are more likely to have cavities, they are said to have a more fertile ground for the development of carious lesions. This happens when the enamel is thin and less resistant to acid attack of bacterial plaque. Similarly, teeth fillings (amalgams and / or composites, crowns) and old frosted foods retain more easily make brushing less effective and promote the formation of bacterial plaque.


Some foods are rich in acidic (fruit juice, sodas) and contribute to weaken the tooth enamel dematerializing them. Other rich in sugars (candy, chips, and crackers) are used by bacteria which, by assimilating them, grow (increase in plaque) and then turn them into acid waste responsible for the demineralization of the tooth enamel.

After your tooth gets decayed there is a need of tooth replacement if you want to smile in public and take the taste of food again.


The development of caries requires time and involves several steps. The four development stages of decay:

1. Destruction of enamel

Acids from bacteria or food begin to dematerialized enamel. This process is completely painless and can be viewed by the dentist during a dental examination (clinical and radiological). At that time decay is still reversible because ions present in saliva (see scale and scaling) can mineralize the enamel surface. This is the regular repetition of the stressor (food, plaque) that will allow the process of demineralization and thus continue to grow the bacteria to the tissues underneath the enamel of the tooth.

2. Reached the dentin

That’s when the tooth becomes sensitive to hot, cold, sweet and acid: one speaks of pain caused. Dentin is less mineralized than enamel, it is faster demineralization and thus the decay will spread and grow faster in the tooth into the pulp.

3. Invasion of the pulp

This is the stage of ‘toothache’ pain is violent, spontaneous and / or caused by heat, cold. If no treatment is carried out the pulp will die, gradually become necrotic. The pain ceases after a time may give the impression that all is well.

4. Invasion of surrounding tissue

The bacteria are present throughout the pulp and will move toward the tip of the root and reach through the apical foramen (see the anatomy of the tooth) and the surrounding tissue (gums, bone, and ligament). Be formed in the longer term an abscess and / or cyst very painful at the end of the root. This infection can spread, or to adjacent tissues and give a “classy” (cellulite) or the whole body via the blood vessels and be responsible for infection of other body parts (eyes, lungs, heart, kidneys, and joints).