USING A HOMEMADE TOOTHPASTE CAN HELP REMINERALIZE, WHITEN, AND STRENGTHEN YOUR TEETH. Even if you are purchasing a natural toothpaste you should check out the label. It’s probably got glycerin. Glycerin keeps the toothpaste smooth and holds it together, but it also creates a strong coating on the teeth that can make remineralization difficult. In fact, according to Dr. Ramiel Nagel of Cure Tooth Decay, it can take up to 30 days of not using glycerin for it to completely wash.