Tom's of Maine uses Sodium Laurel Sulfate which is bad (irritanting chemical, maybe cancer-causing?) It's the foaming agent. Weleda is the only toothpaste I've seen at the store that doesn't have it but I don't like the way it works. I like Young Living (Essential Oils) "Dentarome" toothpaste myself although it is pricey so I probably won't use it forever. www.youngliving.com
My mom has been using Miracle II soap as toothpaste for a few months; she recently went to the dentist for her check-up and he was amazed at how healthy her gums where, he said they had improved since last time (she has average gums, now she has above-average).
I believe Hulda Clark has something she recommends for how to clean teeth, but I can't remember what it is. You can find it on this site (or her site).