Oral biopsy, or oral biopsy, is a surgical procedure that involves removing suspected diseased or normal tissue from the oral cavity using a scalpel or a biopsy instrument and sending it to the Department of Pathology for microscopic or immunohistochemical examination. It is the gold standard for disease diagnosis and can confirm a wide range of diseases, such as common squamous cell carcinomas of the oral cavity or benign tumors or cancers of glandular origin of the oral cavity. It also includes common oral mucosal diseases such as precancerous lesions like leukoplakia, erythema, and lichen planus. Oral biopsy is also the standard for the diagnosis of Sjögren’s syndrome, and biopsy of the labial glands is one of the most important indicators for the diagnosis of Sjögren’s syndrome.