Gap in lower teeth is cutting my tongue after scaling. How can I make it stop?

I would suggest you see your dentist and have him/her smooth your teeth or at least check the areas that bother you. 

It is a good thing that you had the scaling done. Your gums are the foundation on your mouth and periodontal disease leads to bone/tooth loss. Keep it in check and go back for cleanings every 3-4 months. Also ask your dentist about bonding the lower front teeth to close the space a bit and smooth out the sharpness. Bonding is applying tooth colored filling material to the teeth. It is used in fillings and fixing chipped teeth. If there is significant gum recession in the area, a gum graft is needed to replace the gum tissue. It is painful and doesnt alway work. Go back to your dentist and discuss the situation with them. 

Hi, thanks for sending your question. I am sorry you are having issues with sensitivity on your tongue. All the concerns you raised are signs of periodontal disease, or gum disease. Its important to see a dentist in order to access the periodontal concerns and have treatments done. All the best