Why do i involuntarily clench my teeth at night?

Many reasons: Everyone does some form of grinding at night. Some worse than others. Stress levels, and your bite are 2 common reasons for this, but there are other unknown factors that can cause your brain to signal yor jaw muscles. If you know you are grinding, talk to a dentist about a nightguard to protect your teeth from wearing down. Sometimes they even help you stop the habit!

Stress or Bite Prob.: Clenching is often a subconscious release of daily stress. If you have a stress-filled day, try not to watch the news or read anything intense or work related prior to going to sleep. Take about 1/2 hour to wind down, read something light, or watch a comedy on tv. Relaxation techniques may work or you may need a bite guard constructed by your dentist. Also you may need a bite adjustment.