Tumour diseases
If the control mechanisms controlling cell growth, division and differentiation get out of control, the result is a growth (tumour, neoplasia). Tumour cells grow independently and continuously. They do not cease their growth and no longer react to the organism's control signals. They damage the entire organism through their position in the body (crowding of healthy organs), their growth behaviour (penetrating growth) or their metabolic products (hormones, toxins, antigens).
Tumours are generally differentiated into benign or malignant tumours. In this case, however, “benign” does not mean that these tumours cannot also be lethal; the terms “benignity” and “malignity” rather denote special, fine-tissue tumour properties.
Benign tumours grow slowly, are delineated from other tissue (usually by a connective tissue capsule), do not penetrate vessels, do not infiltrate other tissue, do not form metastases and are histologically differentiated (i.e., they often look like healthy tissue). But even these can cause life-threatening complications if they crowd out healthy tissue.
Benign tumours
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One benign tumour in the mouth's mucosa is the fibroma. It grows slowly (over many months or years) and does not cause pain.
Smaller, benign tumours are removed by excision. The effected piece of tissue is removed in its entirety and subjected to fine-tissue examination in a pathological laboratory.
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Malignant tumours
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Malignant tumours are unclearly delineated, penetrate vessels easily, infiltrate and destroy other tissue, form metastases and are histologically undifferentiated (do not look like normal tissue). Due to metastases formation and their aggressive growth, oral mucosa tumours may have a lethal effect.
Tumours occurring relatively frequently in dental medicine are carcinomas of the mucosa, tumours of the jaw bone, fibromas and haemangiomas (in the blood vessels of the jaw and face area). Tumours can also develop from dental tissue. Particular mention must be made of the adamantinoma (ameloblastoma). This is a semi-malignant tumour with its origins in the cells of the enamel epithelium.
A tumour-like, cystic deformity, which can contain all dental hard substances, is the odontoma.
If a tumour cannot be classified through its appearance or other properties, a fine-tissue examination in a laboratory (at the pathologist) is required. This requires the sampling of tissue. The surgical removal of a small piece of diseased tissue is called a sample excision. The lab's histological findings serve to back up the diagnosis.
