Teeth grinding is a direct result of stress. This is your bodies way of telling you that you need to take stock of your life and reduce your stress. If you do not reduce your stress or realise that you are stressed the jaw-grinding can become a chronic problem. Go and see your local physio who specialises in stress management, or get the book "How not to stress-out" or "Ashes to ashes, overcoming all forms of loss" both available on Amazon and written by Lesley Meyer.