The last human third molar to erupt (upper and lower 8, a total of 4) is called wisdom tooth, wisdom tooth eruption time is about 16-25 years old, with the human food fine, stimulation of the mandible gradually weakened, the mandible wisdom tooth development space is insufficient, resulting in wisdom tooth occurred in different directions of tilt, or even ambush obstruction. The tilting and obstruction of wisdom teeth make local food embedding and not easy to clean, while the occlusal trauma of the gum tissue around the wisdom teeth by the opposite tooth causes recurrent episodes of pericoronitis of wisdom teeth. It can also cause complications such as maxillofacial interstitial infection and osteomyelitis. Timely extraction of wisdom teeth (blocked teeth) can reduce and prevent a series of complications caused by pulpitis and pericoronitis due to decay of wisdom teeth and neighboring teeth.