Tophaceous pseudogout is a disease of calcium pyrophosphate dehydrate （CPPD） deposition of joints. We report an unusual case of calcium pyrophosphate dehydrate involving the temporomandibular joint （TMJ）. The patient was a 48-year-old male with the chief complaint of pain in the left TMJ. Biopsy was performed under general anesthesia, and a diagnosis of contradiction as tophaceous pseudogout was obtained. When diagnosing nodular masses with calcification around the temporomandibular joint, it may be necessary to consider this disease as one of differentiation.
Methotrexate-associated lymphoproliferative disorder （MTX-LPD）, which may develop in the oral cavity, is known to be associated with the administration of methotrexate. We herein report a case of MTX-LPD that developed in the buccal mucosa. The patient was a 64-year-old woman who had undergone long-term methotrexate treatment for rheumatoid arthritis and who complained of ulcer formation in the bilateral buccal mucosa. The pathological diagnosis was diffuse large B-cell lymphoma with Epstein-Barr virus-positive cells. The lesions improved following the withdrawal of methotrexate. The development of MTX-LPD in the buccal mucosa is very rare.
Plasmacytosis is a chronic inflammatory disease that occurs in a body opening, such as the oral cavity or vulva, and is accompanied by mucosal redness, erosion, and edematous changes. Histopathological examination has revealed epithelial thinning and plasma cells. Plasmacytosis is a relatively rare disease with infiltration. Herein, we report a case of open-cell plasmacytosis that was successfully treated with corticosteroids despite difficulties in diagnosis and treatment.