Caries is nothing but the result of demineralization of teeth. As this occurs, the tooth enamel is softened, appearing small white spots on its surface. If demineralization progresses, the enamel is lost irreversibly and a small, dark initially painless cavity forms: caries has appeared.
Pierced enamel, dentin decay penetrates and gets closer to the dental pulp of the tooth where the nerve root is. From a certain point, the person feels discomfort or pain to certain stimuli (foods or cold, hot or sweet drinks, for example). It is usually at this point, once the decay has already caused significant damage to the tooth when it comes to the dentist.
If tooth decay continues to progress, eventually produce inflammation of the pulp (pulpitis), characterized by persistent dental pain. The pus can cause a compression of the nerve root, causing intense pain and spreading to neighboring areas and can be difficult to identify exactly what the diseased tooth. This pain usually improves by applying cold in the area, so it is not uncommon to see a person go to the dentist with a cold bottle of water in hand. Generally, at this point, the involvement of the pulp is irreversible.
The process can lead to the formation of a dental abscess, a real pocket of pus that extends beyond the damaged tooth and may affect bone anchorage area and soft tissues of the mouth to become inflamed. Sometimes the pus gets its way outward through a fistula in the soft tissues. A visible discharge then occurs and pain is relieved considerably.