There are two types — one where you gnash and clench your teeth while awake — awake bruxism — and one where you clench and grind your teeth at night, termed sleep bruxism. Often, daytime teeth grinding occurs when you are under stress, experiencing anxiety, or it may be simply a bad habit.
While common in adults, this condition should be taken very seriously in children and teens. Some researchers estimate that as many as 20–30 percent of children grind their teeth. Often, this can be an early sign that their top teeth don’t properly align with their bottom teeth, and a dentist or orthodontist should be consulted as quickly as possible.
Stress is one of the main reasons for this phenomenon, so that's why it's often called the dental syndrome of modern society.
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