Wisdom tooth pericoronitis often appears as an acute inflammation. At the onset of the disease, the gum on the affected side is often swollen and uncomfortable, and the pain is increased when opening the mouth, swallowing, or chewing. If the disease continues to develop, the local pain increases and can radiate to the ipsilateral side of the head and face. When you examine yourself in the mirror, you can find that the mucosa at the very back of the tooth is red and swollen, and it hurts when you touch it with your hand. Sometimes the patient can also see a part of the wisdom tooth, and pus overflow can be seen in the gum pocket above the crown of the tooth. If the inflammation is not controlled in time, it often invades the nearby chewing muscles, resulting in the inability to open the mouth and even the occurrence of dental closure. In severe cases, the inflammation can also cause peri-maxillary space infection or osteomyelitis. The systemic symptoms are fever, chills and general malaise of varying degrees. The total white blood cell count increases and the percentage of neutrophils rises.