It is found by family members who grind their teeth loudly when they sleep at night, or by people who sleep in the same dormitory, like college students. When you check the teeth, you should look at two places, one is the teeth, the tip of the tooth is still there, always grinding the tip of the tooth is worn out, the crest of the tooth still exists, a look at the teeth are very flat, it is definitely caused by grinding teeth, and then check the temporomandibular joint, long-term grinding of teeth is often wear and tear deformation of the joint. Through these two aspects to check, and then is through the electromyography to check, you can put the chewing muscle with electromyography test, appear different waveforms, look at the muscle force, and myoelectricity situation, through these methods can also be auxiliary examination, reference use.