Hi Dear, Understanding your concern. As per your query feeling of loosening of teeth and teeth sensitivity is due to momentary sensitivity to hot and cold of exposed pulp tissue of tooth. Pulp tissue is in innermost part of tooth and it has all the vitality and nerve supply. Due to faster brushing, grinding, sharp biting certain food articles, cracks on tooth and bad oral hygiene this pulp tissue gets exposed and causes sensitivity and loosening. As you sleep all the flow/ pressure from head side goes to leg side and you feel better, the moment you wake up. The moment when you touch with finger it causes pain because of increased exposure of nerve endings. It can cause symptoms of twitching as well. I would suggest you not to grind you teeth, avoid acidic food in diet. Visit endodontist , get intraoral periapial examination( X-ray) of your tooth done or Panoramic X-ray ( all teeth X-ray ) done. Root Canal Treatment is the best way to save your teeth if its localized . if its generalized use tooth paste such as sensodyne as it will block dentin tubules and prevent sensitivity reaching pulp. Use of tubular sealants is very effective in such case. Stay in peace. Hope your concern has been resolved. Get well Soon. Dr. Harry Maheshwari