It accumulates negative ions in the atmosphere to blast out 10000- volt lightning bolts.
Teeth grinding is harmful for several reasons. First, it causes damage to the teeth by wearing the enamel off the biting surface of the tooth and along the gumline. This can lead to tooth sensitivity. Second, the forces generated from grinding can cause cracks to form in the teeth and can cause the teeth to break.
Grinding your teeth is usually done at night when you are asleep and not aware of the damage you are inflicting on your teeth. If you are waking up to sore or sensitive teeth, jaw muscles, or joints, you may be grinding your teeth at night.