LPT: Buy Prescription Strength Fluoride Toothpaste From Your Dentist If you want to strengthen the enamel in your teeth and want more than consumer brands of toothpaste and mouthwash can offer, your dentist can sell you prescription strength fluoride toothpaste that can be as strong as 1% fluoride. The one I use is called Prevident and costs $17 a bottle. I brush with it instead of my normal toothpaste right befo…