The Best Over-the-counter Night Guard? I just found out that I grind my teeth at night. I have a bruised ligament under one of my molars and I won't be able to get a dentist prescribed guard for another couple of weeks. Is there a recommended guard I can buy from Walgreens to help the ligament heal before I get a real one? I also leave for basic training in a month and I think I can bring them there.