The main reasons for grinding teeth at night are as follows: 1, suffering from dental diseases in the mouth, such as suffering from dental caries, pulpitis, periodontitis and other diseases. As the teeth appear swollen and painful discomfort during sleep, it will lead to the phenomenon of night grinding teeth. In addition, some people have uneven tooth wear, the tip of individual teeth exist cusp early contact, cusp early contact is also a major cause of night grinding teeth. 2, due to the lack of good oral hygiene cleaning before going to bed, the surface of the teeth and tongue surface accumulation of a large number of food residues. Food residues will stimulate the taste buds and stimulate the taste nerve, which will lead to night grinding of teeth when sleeping. 3, mainly seen in people with severe calcium deficiency and vitamin D deficiency, such as those suffering from rickets, will also appear the phenomenon of night grinding of teeth. 4, if you eat indigestible food before going to bed, or the patient himself suffers from gastric ulcer, indigestion and other diseases, resulting in frequent abdominal pain and bloating during sleep, will also lead to night grinding teeth.