In normal work, patients often have this question: “Is there surgery in dentistry? Can tumors still grow in the mouth?” . Even doctors and nurses from other departments would also ask similar questions. It seems that the publicity of stomatology is not as popular as expected. So, how exactly is the division of stomatology, and what diseases should be treated in oral surgery? Oral surgery, also known as oral and maxillofacial surgery, can be seen by the literal meaning of the word, it includes three aspects: oral, jaw, face. The oral cavity refers to the lips, cheeks, tongue, palate, gums, teeth, etc., which are the hard and soft tissues in the mouth; the jaw refers to the upper and lower jaws where the teeth are located, as well as the zygomatic bone, zygomatic arch, palate, butterfly bone, temporal bone, nasal bone, etc., which are the bones below the eyebrow arch and above the chin; the face refers to the soft tissues outside the hairline, around the eyes, around the ears, under the jaw and in the neck area. If you have the following conditions, you need to go to oral surgery. That is: trauma to the face and neck, maxillofacial fractures; occlusal deformities that require surgical treatment; facial and neck masses, including benign and malignant tumors; teeth that need to be extracted; dental implants and pre-implant bone grafting and soft tissue repair; temporomandibular joint disorders that require surgical treatment, etc. Some people may say that some diseases can be treated in other departments, so why do they have to be treated in oral surgery? Yes, oral surgery has crossover with other departments, but because of its special anatomical structure, it has its own special characteristics. For example, parotid area tumor, which is located in front of the ear and under the earlobe, is commonly known as tumor on the cheek. Because of the special structure of facial nerve, if facial nerve dissection cannot be performed before removing the tumor, it is easy to damage the facial nerve and thus lead to facial palsy. Without understanding the nature of the tumor, pleomorphic adenomas such as those in the parotid area, which often do not have an intact envelope and are multi-centric in growth, may not only damage the facial nerve but may also cause multiple recurrences if they are simply removed. We have seen cases of pleomorphic adenomas that have recurred several times, and the patients even pleaded with their doctors before surgery that they would rather have the facial nerve removed than operate again. This shows how important the specialist treatment is. Therefore, we hope to provide the appropriate knowledge of oral surgery here so that you can make the appropriate choice and get better treatment when you visit us.