Here is a great article for WedMD.
Do Children Grind Their Teeth?
The problem of teeth grinding is not limited to adults. Approximately 15% to 33% of children grind their teeth. Children who grind their teeth tend to do so at two peak times -- when their baby teeth emerge and when their permanent teeth come in. Most children lose the teeth grinding habit after these two sets of teeth have come in more fully.
Most commonly, children grind their teeth during sleep rather than during waking hours. No one knows exactly why children grind their teeth but considerations include improperly aligned teeth or irregular contact between upper and lower teeth, illnesses and other medical conditions (such as nutritional deficiencies, pinworm,
allergies, endocrine disorders), and psychological factors including anxiety and stress.
Grinding of the baby teeth rarely results in problems. However, teeth grinding can cause jaw
pain, headaches, wear on the teeth, and
TMD. Consult your dentist if your child's teeth look worn or if your child complains of tooth sensitivity or pain.
Specific tips to help a child stop grinding his or her teeth include:
No intervention is usually required with preschool-age children. However, older children may need temporary crowns or other methods, such as a night guard, to prevent the grinding.
