Children grinding their teeth at night may be caused by dental dysplasia, mental factors, poor nutrition and other reasons. 1. Dental dysplasia: children’s teeth are not aligned, teeth bite obstacles and other reasons easily caused by grinding teeth at night. 2. Mental factors: children are too excited to sleep at night or parents reprimanded, resulting in anxiety, anxiety and other emotions, so that the cerebral cortex excitation, inhibition imbalance, inducing irregular contraction of the chewing muscles or spasm, the emergence of nighttime teeth grinding. 3. Poor nutrition: children usually picky eaters cause the intake of nutrition is not balanced, resulting in a lack of trace elements, vitamins, etc., so that the chewing muscle contraction, the emergence of the case of teeth grinding in bed at night. Poor digestive function, intestinal parasites and other factors can also lead to children sleep at night grinding teeth, parents are advised to take their children to the hospital for a comprehensive examination in a timely manner, under the guidance of the correct treatment.