I'm a dentist, and I use this toothpaste. Traditionally, I'd recommended Prevident 2000 or Gelkam to patients who are cavity prone or have dry mouth. However, Dr. Jeff Brucia at FACE recommended Enamelon + MI paste as a combination for dry mouth or remineralization. After reading a few studies, I started recommending this to my patients (after testing it out on myself). [...] (here's one study). Enamelon is the only toothpaste that I know of (as of this writing) that has Activated Calcium Phosphate (ACP). I recommend that my patients use it exclusively, as the bioavailability of ACP is topical (not systemic). I like that it doesn't have artificial colors, microbeads (Crest, Colgate [...]/), and too much artificial or gimmicky things. This is fairly gentle toothpaste--*no abrasive* (just looked up the MSDS), ACP, some stannous fluoride (not a lot), a mild flavor, and no fancy coloring...and NO SODIUM LAURYL SULFATE (a known tissue irritant)! This is good for: 1. Reversing/preventing acid damage (due to the stannous fluoride effect). 2. Minimizing sensitivity, especially associated with whitening or recession (due to ACP). 3. Reversing/remineralizing early cavities (due to ACP and stannous fluoride). 4. Dry mouth/older patients (due to ACP and fluoride) This does nothing for: 1. Gums. No toothpaste really does anything for your gums. Get floss, a waterpik, or some chlorhexidine oral rinse. 2. Whitening teeth. Actually, I'd avoid any "whitening toothpaste" as it just has extra abrasive compound and free radicals. If you're going to whiten your teeth, do it properly with custom whitening trays and buffered Whitening solution. Regarding turning your teeth brown: Very unlikely. If this toothpaste "turned your teeth brown," you likely have something else that happened (diet (tea, coffee, red wine, tobacco, berries) exposure to lots of minerals in tap water; swimming pool chlorine; something that killed bacteria in your mouth..) While stannous fluoride can turn teeth brown, this particular toothpaste doesn't have a large amount of it. In any case, an staining from this toothpaste should be fairly easily removed by a trained dental professional. ps. Anyways, I just placed another order for this (for a patient) and will likely be recommending this toothpaste as my toothpaste of choice (aside for kids too young to spit).