The common causes of children grinding their teeth in the middle of the night and tossing and turning in their sleep are mental factors, nutritional deficiencies and parasitic infections. 1. Mental factors: If a child is verbally abused, physically punished or frightened before going to bed, these will cause some mental stimulation to the child. Even in the middle of the night, these mental stimuli retained in the subconscious mind will cause the brain center to send out some abnormal instructions, such as allowing the trigeminal nerve to innervate the bite muscle movement, the bite muscle twitching, it will grind teeth. 2. Nutritional deficiencies: If a child suffers from a nutritional imbalance such as a lack of calcium or potassium, the nerve excitability will increase, so he will grind his teeth when he sleeps at night. 3. Parasite infection: parasites love to move at night, if the parasites move a lot in the middle of the night when the child sleeps, the stimulated muscles may reflexively spasm, thus producing the phenomenon of teeth grinding and tossing and turning. If a child grinds his teeth in the middle of the night and tosses and turns in his sleep, the child should be taken to the hospital in time to see a doctor to clarify the cause of the disease and then standardize the treatment.