Probably, there cod be so.e unresolved issues due to which you are always in some thought process that could cause you tbis habit.

Hi, thanks for your approach. Normally I think most of them will experience biting and pressing the teeth(lower teeth pressing upper teeth) (both). But both is done for feelings (negative) like frustration, anger, stress, remembering of some incidence stored in subconscious level. this behavior might occur in night time(sleeping) or during the time when you are recalling the incidence in which without your knowledge your body action will be thrown in this way. yes its better you visit the psychologist, counselling will help you to handle and also overcome the issues. In the mean time follow meditation, stress relief techniques which is comfortable for you. I think there is some stressful or negative situation you are experiencing (ed). stay positive. take care.

Dear friend, I understand that pressing teeth is biting teeth. Since you are doing this mostly at nights, there is some unresolved anger or frustration in mind. Relax your mind. While sleeping follow some relaxation techniques. There are plenty of relaxation techniques available in the internet. Follow any one which is comfortable to you. For further assistance feel free to contact me. Wishes