You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is Plasma cell gingivitis and explain in detail?
Plasma cell gingivitis is a rare condition, appearing as generalized erythema (redness) and edema (swelling) of the attached gingiva, occasionally accompanied by cheilitis (lip swelling) or glossitis (tongue swelling). It is called plasma cell gingivitis where the gingiva (gums) are involved, plasma cell cheilitis, where the lips are involved, and other terms such as plasma cell orifacial mucositis, or plasma cell gingivostomatitis where several sites in the mouth are involved. On the lips, the condition appears as sharply outlined, infiltrated, dark red plaque with a lacquer-like glazing of the surface of the involved oral area.

Signs and symptoms
Plasma cell gingivitis appears as mild gingival enlargement and may extend from the free marginal gingiva on to the attached gingiva. Sometimes it is blended with a marginal, plaque induced gingivitis, or it does not involve the free marginal gingiva. It may also be found as a solitude red area within the attached gingiva (pictures). In some cases the healing of a plaque-induced gingivitis or a periodontitis resolves a plasma cell gingivitis situated a few mm from the earlier plaque-infected marginal gingiva. In case of one or few solitary areas of plasma cell gingivitis, no symptoms are reported from the patient. Most often solitary entities are therefore found by the dentist.The gums are red, friable, or sometimes granular, and sometimes bleed easily if traumatised. The normal stippling is lost. There is not usually any loss of periodontal attachment. In a few cases a sore mouth can develop, and if so pain is sometimes made worse by toothpastes, or hot or spicy food. The lesions can extend to involve the palate.Plasma cell cheilitis appears as well defined, infiltrated, dark red plaque with a superficial lacquer-like glazing. Plasma cell cheilitis usually involves the lower lip. The lips appear dry, atrophic and fissured. Angular cheilitis is sometimes present.Where the condition involves the tongue, there is an erythematous enlargement with furrows, crenation and loss of the normal dorsal tongue coating.

Causes
Plasma cell gingivitis and plasma cell cheilitis are thought to be hypersensitivity reactions to some antigen. Possible sources of antigens include ingredients in toothpastes, chewing gum, mints, pepper, or foods. Specifically, cinnamonaldehyde and cinnamon flavoring are often to blame. However, the exact cause in most is unknown.

Diagnosis
Histologically plasma cell gingivitis shows mainly plasma cells. The differential diagnosis is with acute leukemia and multiple myeloma. Hence, blood tests are often involved in ruling out other conditions. A biopsy is usually taken, and allergy testing may also be used