Wisdom teeth are the third molars that grow in the innermost part of our mouth. During the evolution of human beings, as the food becomes more and more refined, the jaw bone needs less and less force to bear, so that the jaw bone evolves and develops smaller and smaller, while the teeth are still this size, resulting in insufficient eruption position of the teeth, which is the main reason for the abnormal eruption position of wisdom teeth. This is the main reason for the abnormal eruption position of the wisdom teeth. “The use of in and out” is a universal law in biological evolution, and the wisdom teeth are an excellent example of this. Why do wisdom teeth become inflamed and painful? Most of them are due to inflammation of the surrounding gums. Secondly, it affects the second molar in front of it, causing caries and even pulp inflammation of the second molar. When the wisdom tooth is not fully erupted due to the lack of jawbone position, part of the crown is often covered by the gum flap, forming a blind pocket, where the food residue is easy to enter but not easy to discharge, plus the humidity and temperature of the mouth is suitable to provide a good environment for bacteria to grow and reproduce. When the body’s resistance decreases, the area is prone to gingival redness, pain and discomfort, and even spontaneous throbbing pain, radiating to the ear and temporal region, accompanied by ipsilateral lymph node enlargement. The obstructed or misplaced wisdom tooth is easy to make the food residue embedded in the interdental and periodontal gap between the second molar and the wisdom tooth, which is very difficult to remove and often occurs caries. In addition, when the wisdom tooth is obstructed in the process of eruption of the second molar, the osteoclasts attached to the root surface of the second molar will be produced there, which can cause the root to resorb gradually. When do wisdom teeth not need to be extracted? 1. There is enough space for the normal eruption of wisdom teeth, that is, the amount of bone in your jaw is enough to accommodate the wisdom teeth. At the same time, there is a normal occlusal relationship, so it is not necessary to extract. 2.If the second molar is badly decayed and needs to be extracted, the root of the wisdom tooth has not yet been fully formed as confirmed by X-ray, it is possible to keep the wisdom tooth to replace the missing second molar in the future. 3.Wisdom tooth is completely buried in the jawbone without any symptom, it can be kept temporarily and observed regularly. The best time to remove wisdom teeth is between the ages of 16 and 18, because the roots of wisdom teeth are about one-third the length of the normal roots and are not yet fully formed, the roots are shorter and easier to remove, the age is good tolerance, strong healing ability and strong bone tissue repair and regeneration ability. At this age, once the tooth is judged to be obstructed, it should be extracted in time to avoid a series of lesions caused by wisdom teeth. After the extraction of complex wisdom teeth, there is usually swelling, pain, difficulty in opening and painful swallowing, etc. The longer the tooth is extracted, the greater the possibility of swelling in the cheek. Oral anti-inflammatory medication is taken and the swelling usually subsides in 3-5 days.