What is a diseased tooth?

Lesions are closed tissues infected by pathogenic microorganisms, in which pathogenic microorganisms or their toxins can spread to distant organs, leading to diseases in other parts of the body. Generally speaking, a lesion is a limited source of infection, which often manifests as chronic inflammation. It can occur in all parts of the body, but it is more common in the head and face. If the infected tissue is tissue in a tooth or periodontal tissue, the tooth is a diseased tooth. The common odontogenic diseases in oral cavity include periapical periodontitis, pericoronitis, periodontitis, gingivitis, pulpitis, infectious periapical cyst and residual roots and crowns. The diseases caused by odontogenic lesions include acute or subacute bacterial endocarditis, iridocyclitis, iritis, optic neuritis, arthritis, nephritis and so on. The treatment principle of odontogenic lesions is to eliminate the lesions, and there are two main treatment methods: 1) root canal therapy: retaining the affected teeth, removing the pulp tissue through root canal therapy, eliminating the infection source in the root, and restoring the apical tissue to health. 2) Tooth extraction: For teeth that are difficult to be completely cured, teeth with poor curative effect or poor treatment, we should consider the serious consequences of systemic diseases, weigh the pros and cons, and pull them out.