I fell your pain, I have had two root canals. I finally figured out what was hurting my teeth and gums is fluoride. You should see what a farce this "supplement" is, just start by googling what fluoride does to concrete, you will find quite a rabbit trail. I quit using any mouthwash or toothpaste with it and have had much better dental health, less sensitivity and my gums don't recede as much and are getting better instead of worse. Unfortunately I can't get it out of the water, it would be very costly. If I could I would.