The swollen flesh at the very back of the tooth may be wisdom tooth pericoronitis, periodontal abscess, apical periapical inflammation of the tooth. 1. Wisdom tooth pericoronitis refers to the inflammation of the soft tissues around the crown of the tooth in the process of eruption, incomplete eruption and obstruction. Clinically, pericoronitis is more common in mandibular wisdom teeth, followed by maxillary wisdom teeth. 2. Periodontal abscess: Periodontal abscess caused by severe periodontitis will also be manifested as the swelling of the last surface of the teeth. 3. Apical periodontitis: The spread of inflammation in the periapical tissues of the teeth may lead to alveolar abscess, which may also be manifested as swelling of the last side of the teeth. There may be other reasons for the swelling of the flesh at the end of the tooth, it is recommended to go to the hospital in a timely manner, improve the examination to determine the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.