I've been suffering from constant pain for the last 4 years. It started right after the dentist did a preparation for a 3-unit bridge to replace a missing tooth. For two years the dentist was unable to find the cause of the pain and was suggesting various dental procedures including bridge replacement, nerve canal treatment, etc. But none of them helped. I pulled all of my teeth on that side and spent a lot of money. Finally my new dentist suggested to see a neurologist who told me that I sustained an irreversible nerve injury from the numbing shot(s) given to me when I underwent the dental work for the bridge.