Toothpaste is a parity product. That is, the basic ingredient of fluoride is present in the preparation in the same amount in all types of toothpaste. The only difference is some use stannous fluoride (with a tin atom) as opposed to sodium fluoride. Crest toothpaste uses this instead, there are studies that suggest it works better. Other stuff is just additives that may or may not do anything, including peroxides, saltpeter (KNO3, potassium nitrate,) sodas, colors, etc. It's the fluoride that does the dirty work, and all toothpaste sold over-the-counter has the same amounts. Buy the cheapest kind you can get, there's literally no difference.