The situation of gnashing of teeth in the sleep state is caused by the following reasons: 1. Related to dreams, dreaming is caused by active brain cells, things that happen during the day, things that are often worried about are reflected in sleep, and a variety of dreams are formed, such as sad, excited, anxious dreams, etc. The appearance of gnashing of teeth may be caused by arguing with people, hating people and hating things in dreams. Affect the quality of sleep, should make the mind calm, do not stay up late. 2, intestinal parasitic disease, mostly seen in children or adolescents, common clinical symptoms are sleep grinding teeth, itching near the anus, body wasting, etc. 3, children due to the immature nervous system, usually too much pressure on learning, etc. may cause the emotion of grinding teeth. Usually do not stay up late, strengthen nutrition, do not have too much psychological pressure.