Night-time tooth grinding (bruxism) is common in children. Parents often complain of the awful noise made by grinding teeth. Luckily, most children outgrow this habit and do not cause serious damage their teeth. The grinding gets less between the ages 6-9, and children tend to stop grinding between ages 9-12. Occasionally, a parent will notice the teeth wearing down from bruxism. This is more concerning, but even in these cases, the baby teeth will usually fall out without pain or problems, although the teeth are ground down.
We do not know exactly why children grind their teeth at night but one theory is that stress due to a new environment, family changes, changes at school, divorce, etc. cause bruxism. Others think that pressure changes in the inner ear may cause a child to brux and grind from moving their jaw in an effort to relieve this pressure. Perhaps it is just a mechanism for children to allow their growing jaws to accommodate their changing occlusion.
Most cases of childhood bruxism do not require treatment. Excessive wear of the teeth (attrition) that is causing discomfort or threatens to expose the tooth nerve can be treated with fillings, crowns or a mouth guard (night guard) may be used. Mouth guards are a last resort because they are difficult to keep in and must be changed frequently as teeth come and go during childhood. If your pre-adolescent has lost all their primary teeth and is still grinding their permanent teeth, then a bruxism mouth guard is important.