Inflammation after tooth extraction is medically referred to as post-extraction infection, which is mainly divided into acute infection and chronic infection. Acute infection after tooth extraction is actually relatively rare, mostly occurring after the extraction of mandibular obstructive wisdom teeth, which may be caused by improper selection and treatment of the timing of tooth extraction. Chronic infections are more common and are caused by tooth fragments or bone fragments remaining, tartar falling into the extraction socket, or infected granulation tissue not being scraped away. Usually, it is possible to determine whether a tooth is inflamed after extraction based on its clinical manifestations. Acute interstitial infection is the more common type of acute infection after tooth extraction, mainly manifested as restricted opening and painful swallowing, which is often prolonged because it is not easily diagnosed. If the above symptoms appear after tooth extraction, it is considered as acute infection and needs to be treated with incision and drainage and reasonable use of antibacterial drugs. If the post-extraction manifests as uncomfortable extraction wound and examination reveals poorly healed extraction wound, redness, flaccidity, edematous inflammatory granulation tissue proliferation, or even purulent discharge, then chronic infection is considered. In this case, the “culprit” of these infections should be cleaned under local anesthesia, and then a thorough scraping and rinsing of the extraction sockets should be performed to scrape the foreign body and inflammatory granulation tissue, and to re-form the blood clot in the alveolar sockets for final healing.